Question

7. What is the sum of 2a2 + 4ab – 3b2 and -3a2 – 6ab + 9b2?

A. -5a2 – 10ab + 12b2
B. 5a2 + 10ab – 12b2
C. –a2 – 2ab + 6b2
D. a2 + 2ab – 6b2

8. Three sides of a triangle measures (6p + 10) cm, (8p – 5) cm and (-12p + 20) cm. What is its perimeter?

A. (26p + 35) cm
B. (26p – 25) cm
C. (2p + 25) cm
D. (2p – 25) cm

9. What is the difference of 18x⁵and 10x⁵?

A. 8x5
B. 28x5
C. -8x5
D. -28x5

10. What is the difference if 4x²– 7x + 9 is subtracted from 5x²+ 14 X – 2?

A. x2 – 21x + 11
B. x2 + 21x + 11
C. x2 + 21x – 11
D. x2 – 21x – 11​

Answer 1

Answer:

7.(2a2+4ab-3b2)+(-3a2-6ab+9b2)=2a2+4ab-3b2-3a2-6ab+9b2

=-a2-2ab+6b

8.perimeter of the triangle is (6p+10)cm+(8p-5)cm+(-12p+20)cm=(6p+10+8p-5-12p+20)cm=(2p+25)cm

9. 18x5-10x5=(18-10)x5=8x5

10. (5x2+14x-2)-(4x2-7x+9)=5x2+14x-2-4x2+7x-9

=x2+21x-11

Answer 2

$\huge\fcolorbox{black}{lime}{❥ᴀ᭄ɴsᴡᴇʀ}$

7.(2a2+4ab-3b2)+(-3a2-6ab+9b2)=2a2+4ab-3b2-3a2-6ab+9b2

=-a2-2ab+6b

8.perimeter of the triangle is (6p+10)cm+(8p-5)cm+(-12p+20)cm=(6p+10+8p-5-12p+20)cm=(2p+25)cm

9. 18x5-10x5=(18-10)x5=8x5

10. (5x2+14x-2)-(4x2-7x+9)=5x2+14x-2-4x2+7x-9

=x2+21x-11