The gcf of any two even numbers is always even

The equation x2 – 1x – 90 = 0 has solutions {a, b}. what is a + b?

Angle xyz is formed by segments xy and yz on the coordinate grid below: a coordinate plane is shown. angle xyz has endpoints at 3 comma negative 1 and 6 negative 2 and 3 comma negative 3 and measures 36.87 degrees. angle xyz is rotated 270 degrees counterclockwise about the origin to form angle x′y′z′. which statement shows the measure of angle x′y′z′?

Which of the following is the explicit rule for a geometric sequence defined a recursive formula of a -5a for which the first term is 23?