Question

Factor completely: 40xy^2 - 36x^2y.

A. 4xy(9y - 10x)

B. 4xy(10y - 9x)

C. Prime

D. 4xy(10x - 9y)

Answer 1

ok... whats th highest common factor of 40 and 36..?

then whats the highest common factor of x and x^2

lastly what is the highest common factor of y^2 and y?

these values will be outside the brackets

Answer 2

4,X,Y

Answer 3

great so

\[4 \times 10 \times x \times y \times y = 40xy\]

and

\[4 \times - 9 \times x \times x \times y = -36x^2y\]

so if 4xy is outside the brackets

what do you think is inside the brackets..?

for each expanded expression just cross out 4, x and y

Answer 4

10y-9x?

Answer 5

thats correct... so the answer is

4xy(10y - 9x)

simple as that