Help plz: 7. Add or subtract the following polynomials:
a. 5x^2 + 3y^3 - 4x^2 =
b. y^3 + 2y^3 - 8 + 2 =
c. 9 - 3x - 4x + 2x - 12 =
d. -6t + 4t^2 - 6 + 7t - 4t^2 =

4 and 5)16.97 or 12√2

6)15.59 or 9√3

7)y = 15.59 or 9√3     x =27

8)17.80

d

step-by-step explanation:

i used the pitagoras theoreme

1. 180°. the sum of the interior angles of a triangle is 180°, for the equilateral triangle that it has three equals side is 60°+60°+60°=180°.

2. 60°. each interior angle of a equilateral triangle is 60°

3. 120°. the measure of ∠m is 120°, the sum of the angles ∠m and ∠n is equal to 180°. so, in order to find the measure of ∠m, we have ∠m+∠n=180° > ∠m=180°-∠n > ∠m=180°-60°=120°.

4. 360°. the sum of the exterior angles of an equilateral triangle is ∠m+∠r+∠x=120°+120°+120°=360°. the exterior angles of any triangle always add 360°.