Call test:

    NSArray *points = @[[NSValue valueWithCGPoint:CGPointMake(40, 612)],
                        [NSValue valueWithCGPoint:CGPointMake(379, 788)],
                        [NSValue valueWithCGPoint:CGPointMake(0, 352)]];

//    NSArray *distances = @[@(13.535637), @(46.931522), @(51.585461)];
    NSArray *distances = @[@(349.9057), @(352.84134), @(353.37515)];

    TriangularisationMapView *v = [[TriangularisationMapView alloc] initWithFrame:CGRectMake(0, 0, 600, 600) points:points andDistance:distances];
    [[self view] addSubview:v];

------------------------------------------------------------------------------------------------------------------------

@interface TriangularisationMapView : UIView
-(id)initWithFrame:(CGRect)frame points:(NSArray *)points andDistance:(NSArray *)distance;

@end



------------------------------------------------------------------------------------------------------------------------

#import "TriangularisationMapView.h"

@interface TriangularisationMapView ()

@property (nonatomic, assign) CGPoint  pointA;
@property (nonatomic, assign) CGPoint  pointB;
@property (nonatomic, assign) CGPoint  pointC;
@property (nonatomic, assign) float    distanceToA;
@property (nonatomic, assign) float    distanceToB;
@property (nonatomic, assign) float    distanceToC;

@property (nonatomic, assign) CGPoint  finalPoint;
@end

@implementation TriangularisationMapView

-(id)initWithFrame:(CGRect)frame points:(NSArray *)points andDistance:(NSArray *)distance
{
    self = [super initWithFrame:frame];
    if (self)
    {
        [self setBackgroundColor:[UIColor whiteColor]];
        _pointA = [[points objectAtIndex:0] CGPointValue];
        _pointB = [[points objectAtIndex:1] CGPointValue];
        _pointC = [[points objectAtIndex:2] CGPointValue];

        _distanceToA = [[distance objectAtIndex:0] floatValue];
        _distanceToB = [[distance objectAtIndex:1] floatValue];
        _distanceToC = [[distance objectAtIndex:2] floatValue];
    }
    return self;
}

- (void)drawRect:(CGRect)rect
{
    [self addCircleNb:0 withCenter:_pointA andRadius:_distanceToA];
    [self addCircleNb:1 withCenter:_pointB andRadius:_distanceToB];
    [self addCircleNb:2 withCenter:_pointC andRadius:_distanceToC];

    [self calculatePosition];
}

-(void)calculatePosition
{
    CGPoint P2MinusP1 = CGPointMake(_pointB.x - _pointA.x, _pointB.y - _pointA.y);
    CGPoint P3MinusP1 = CGPointMake(_pointC.x - _pointA.x, _pointC.y - _pointA.y);
    CGFloat magP2MinusP1 = sqrt(pow((P2MinusP1.x), 2) +  pow((P2MinusP1.y), 2));
    CGPoint eX = CGPointMake(P2MinusP1.x / magP2MinusP1, P2MinusP1.y / magP2MinusP1);
    CGFloat i = eX.x * P3MinusP1.x + eX.y * P3MinusP1.y;
    CGPoint eXTimesI = CGPointMake(eX.x * i, eX.y * i);
    CGPoint P3MinusP1MinusITimesEX = CGPointMake(P3MinusP1.x - eXTimesI.x, P3MinusP1.y - eXTimesI.y);
    CGFloat magP3MinusP1MinusITimesEX = sqrt(pow(P3MinusP1MinusITimesEX.x, 2) + pow(P3MinusP1MinusITimesEX.y, 2));
    CGPoint eY = CGPointMake(P3MinusP1MinusITimesEX.x / magP3MinusP1MinusITimesEX, P3MinusP1MinusITimesEX.y / magP3MinusP1MinusITimesEX);
    CGFloat j = eY.x * P3MinusP1.x + eY.y * P3MinusP1.y;
    CGFloat x = (pow(_distanceToA, 2) - pow(_distanceToB, 2) + pow(magP2MinusP1, 2)) / (2 * magP2MinusP1);
    CGFloat y = (pow(_distanceToA, 2) - pow(_distanceToC, 2) + pow(i, 2) + pow(j, 2)) / (2 * j) - (i * x) / j;

    _finalPoint = CGPointMake(_pointA.x + x * eX.x + y * eY.x, _pointA.y + x * eX.y + y * eY.y);

    NSLog(@"%f %f", _finalPoint.x, _finalPoint.y);

    UIView *centerView = [[UIView alloc] initWithFrame:CGRectMake(_finalPoint.x-3, _finalPoint.y-3, 6, 6)];
    [centerView setBackgroundColor:[UIColor orangeColor]];

    UILabel *label = [[UILabel alloc] init];
    [label setBackgroundColor:[UIColor clearColor]];
    [label setText:[NSString stringWithFormat:@"Final: {%d,%d}",(int)_finalPoint.x, (int)_finalPoint.y]];
    [label sizeToFit];
    [label setFrame:CGRectMake(_finalPoint.x - ([label frame].size.width/2.0),
                               _finalPoint.y - ([label frame].size.height/2.0-20),
                               [label frame].size.width,
                               [label frame].size.height)];
    [self addSubview:label];
    [self addSubview:centerView];


    [self checkFinalPoint];
}

-(void)checkFinalPoint
{
    float distanceToA2 = [self distanceBetweenPoints:_pointA with:_finalPoint];
    float distanceToB2 = [self distanceBetweenPoints:_pointB with:_finalPoint];
    float distanceToC2 = [self distanceBetweenPoints:_pointC with:_finalPoint];

    float affordableError = 4;
    if (fabs(distanceToA2-_distanceToA) >= affordableError || (fabs(distanceToB2-_distanceToB) >= affordableError) || (fabs(distanceToC2-_distanceToC) >= affordableError))
    {
        NSLog(@"Position Too Much Wrong");
    }

}

-(float)distanceBetweenPoints:(CGPoint)pointA with:(CGPoint)pointB
{
   float square = (pointA.x-pointB.x)*(pointA.x-pointB.x)+ (pointA.y-pointB.y)*(pointA.y-pointB.y);

    return sqrtf(square);
//    NSLog(@"Result: %@", @(sqrtf(square)));
}

-(void)addCircleNb:(NSInteger)nb withCenter:(CGPoint)center andRadius:(CGFloat)radius
{
    //Global Circle
    UIView *aView = [[UIView alloc] initWithFrame:CGRectMake(center.x-radius, center.y-radius, radius*2, radius*2)];
    [aView setBackgroundColor:[UIColor clearColor]];

    //Point Center
    UIView *centerView = [[UIView alloc] initWithFrame:CGRectMake(radius-1, radius-1, 2, 2)];
    [centerView setBackgroundColor:[UIColor blackColor]];
    [[centerView layer] setCornerRadius:1];

    //Center Coordinate Label
    UILabel *label = [[UILabel alloc] init];
    [label setBackgroundColor:[UIColor clearColor]];
    [label setFont:[UIFont systemFontOfSize:10]];
    [label setText:[NSString stringWithFormat:@"{%d,%d}",(int)center.x, (int)center.y]];
    [label sizeToFit];
    [label setFrame:CGRectMake(([aView frame].size.width-[label frame].size.width)/2.0,
                               ([aView frame].size.height-[label frame].size.height)/2.0,
                               [label frame].size.width,
                               [label frame].size.height)];
    [aView addSubview:label];
    [aView addSubview:centerView];

    switch (nb)
    {
        case 0:
            [[aView layer] setBorderColor:[[UIColor blueColor] CGColor]];
            [label setTextColor:[UIColor blueColor]];
            break;
        case 1:
            [[aView layer] setBorderColor:[[UIColor redColor] CGColor]];
            [label setTextColor:[UIColor redColor]];
            break;
        case 2:
            [[aView layer] setBorderColor:[[UIColor greenColor] CGColor]];
            [label setTextColor:[UIColor greenColor]];
            break;
        default:
            break;
    }
    [[aView layer] setBorderWidth:2.0];
    [[aView layer] setCornerRadius:[aView frame].size.width/2.0];

    [self addSubview:aView];
}

@end