Question

9x^2-18xy+5y^2

Answer 1

factor please

Answer 2

one way of tackling these is as follows:

1. this expression involves x and y, so we know the solution has to be of the form: (ax+by)(cx+dy)

2. the coefficient of y^2 is 5 (which is a prime number) and the middle term involving xy is negative, so we know the factorisation must be of the form: (ax-5y)(bx-y)

3. that leaves a and b to be found. the coefficient of x^2 is 9 which can be factored as 1*9 or 3*3. you should be able to solve from here.

Answer 3

(3x+5y)?

Answer 4

we ended up with (ax-5y)(bx-y)

so (3x+5y) cannot be one of the factors - it has to be (3x-5y).
now what is the remaining factor?