Solve each system by elimination.
-7x+9y=16
7x-8y=-8

x=8, y=8. (8, 8).

Step-by-step explanation:

-7x+9y=16

7x-8y=-8

y=8

7x-8(8)=-8

7x-64=-8

7x=-8+64

7x=56

x=56/7

x=8

x= -3 and

step-by-step explanation:

to find the roots of a cubic, use division or factoring to find the factors then set equal to 0. as this is a difference of cubes, it factors into

where a is the cube root of .

here   this is 27 and the cube root of 27 is 3. so we write using the form:

.

set each factor to 0 and solve for x.

x-3=0

x=3

the quadratic expression does not factor and must be solved using the quadratic formula.

where a = 1, b=3, and c=9

this cubic has two complex roots.