3x + y = 15 and y = 2x
The solution, given in (x, y) form is

(3, 6)

Step-by-step explanation:

3x + y = 15

y = 2x

Using substitution:

3x + 2x = 15

5x = 15

x = 15/5

x = 3

y = 2x

y = 2 * 3

y = 6

x = 3

y = 6

= (3, 6)

10a^3+277a^2-132a-792

step-by-step explanation:

(2a+11)(5a-12)(foil)

=10a^2-24a+55a-132 =10a^2+31a-132

(10a^2+31a-132)(a+6)

=10a^3+60a^2+31a^2+186a^2-132a-792 =10a^3+277a^2-132a-792

i hope this is what you are looking for : )