Question

Recall the equation for a circle with center (h,k) and radius r. At what point in the first quadrant does the line with equation y=2.5x+4 intersect the circle with radius 6 and center (0, 4)?


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Answer 1

Equation of a circle centered at (h,k) is:
(x - h)^2 + (y - k)^2 = r^2
Put the values for h, k and r above.

To find the point of intersection of the circle with the line y = 2.5x + 4,
just set y = 2,5x + 4 in the circle equation and solve for x. You will get two values for x. Find the one that lies in the first quadrant. From the x value, put it in the straight line equation and find y.

Answer 2

so is the circle equation (0-h)^2+(4-k)^2=6^2, if so where would I plug in the line equation?