Helllp me asap i don’t understand

To solve the system of equations below, pedro isolated the variable y in the first equation and then substituted it into the second equation. what was the resulting equation? { 5y=10x {x^2+y^2=36

Ade and abc are similar. which best explains why the slope of the line between points a and d is the same as the slope between points a and b?

If abcde is reflected over the x-axis and then translated 3 units left, what are the new coordinates d?