4 = 9 4 + c 4 9 4 = c c = 25 4 So the equation of the tangent to the circle x 2 + y 2 = 25 at the point (3, -4) is y = 3 4 x 25 4 ...

GCSE OCR Other graphs - OCR The equation of the tangent to a circle - Higher The most commonly occurring graphs are quadratic, cubic, reciprocal, exponential and circle graphs. Their equations can ...