HELP PLEASEE no links Select all the shapes that do not have perpendicular sides.
A. Square
B. Equilateral triangle
C. Rectangle
D. Right triangle
E. Acute triangle

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

Marco has $38.43 dollars in his checking account. his checking account is linked to his amazon music account so he can buy music. the songs he purchases cost $1.29. part 1: write an expression to describe the amount of money in his checking account in relationship to the number of songs he purchases. part 2: describe what the variable represents in this situation.

Parabolas y=−2x^2 and y=2x^2 +k intersect at points a and b that are in the third and the fourth quadrants respectively. find k if length of the segment ab is 5.