If a graph fails the vertical line test it's not a function; you can't have a single x map to two ys.
Vice versa, if the graph passes the verticle line test, it's a function.
The horizontal line test tests for injectivity aka one-to-one-ness; it has no bearing on whether something's a function.
Answer:
-5
Step-by-step explanation:
2x+3=-7
2x=-7-3
2x=-10
x=-10/2
x=-5
24²+7²=25²
576+49=625
625=625