Question

Find all points having an x-coordinate of 7 whose distance from the point (4,-2) is 5

Answer 1

Write the equation of a circle with center (4,-2) and radius 5.
Then replace x with 7 and solve for y.

Answer 2

ok

Answer 3

Let the point be (7,y)
\[\sqrt{\left( 7-4 \right)^{2}+\left( y+2 \right)^{2}}=5,\left( y+2 \right)^{2}=25-9=16\]
\[y +2=\pm 4\]
solve for y and get the two values of y.
Then the points are (7,y) and (7,-y)

Answer 4

correction
y means one value
-y means second value