To combine like terms, add or subtract the coefficients (the numbers that come before the variables) of terms that have the same variable raised to the same exponent.

4a⁶ + 4a⁶ = 8a⁶

To multiply binomials, use the FOIL method. FOIL stands for First, Outside, Inside, Last and refers to the position of each term in the parentheses:

(y + 2)(y - 6)
(y x y) + (y x -6) + (2 x y) + (2 x -6)
y² - 6y + 2y - 12
y² - 4y - 12

A cylinder is a solid figure with straight parallel sides and a circular or oval cross section with a radius (r) and a height (h). The volume of a cylinder is π r²h and the surface area is 2(π r²) + 2π rh.

The formula for area is πr²:

a = πr²
a = π(3²)
a = 9π

The area of a trapezoid is one-half the sum of the lengths of the parallel sides multiplied by the height:

a = ½(b + d)(h)
a = ½(9 + 7)(4)
a = ½(16)(4)
a = ½(64) = \( \frac{64}{2} \)
a = 32