Question

Which expression is equivalent to the expression below? 9y^2 + 3y - 4 + 2y - 6y^2 + 1
​


A
3y2+6y−53y^{2}+6y-53y
2
+6y−5
B
3y2+5y−33y^{2}+5y-33y
2
+5y−3
C
15y2+5y−515y^{2}+5y-515y
2
+5y−5
D
15y2+6y−315y^{2}+6y-315y
2
+6y−3


Which expression is equivalent to (5q) (3r - 5qr + 7qr^2)
?
A
10qr+7qr210qr+7qr^{2}10qr+7qr
2

B
15qr−10q2r15qr-10q^{2}r15qr−10q
2
r
C
15qr−25qr+35qr215qr-25qr+35qr^{2}15qr−25qr+35qr
2

D
15qr−25q2r+35q2r215qr-25q^{2}r+35q^{2}r^{2}15qr−25q
2
r+35q
2
r
2

Answer 1

First: 9y^2 + 3y - 4 + 2y - 6y^2 + 1
Combine like terms: (9-6)y^2 + (3+2)y + (-4+1) = 3y^2 + 5y - 3 → choice B.

Second: (5q)(3r - 5qr + 7qr^2)
Distribute: 5q·3r = 15qr; 5q·(-5qr) = -25q^2r; 5q·7qr^2 = 35q^2r^2 → 15qr - 25q^2r + 35q^2r^2 → choice D.