URGENT PLEASE
What is the y-intercept of the graph below

Can someone me with this problem i don't understand i need

The given diagram shows the parts of a right triangle with an altitude to the hypotenuse. using the two given  measures, find the other four.

Right ∆abc has coordinates a(-7, 3), b( -7, 10), and c(-1, 3). the triangle is reflected over the x - axis and then reflected again over the y - axis to create ∆a'b'c'. which are the coordinates of vertex a'?