To factor a quadratic expression, apply the FOIL (First, Outside, Inside, Last) method in reverse.

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.

7a - 4a = 3a

A monomial contains one term, a binomial contains two terms, and a polynomial contains more than two terms.

To factor a quadratic expression, apply the FOIL method (First, Outside, Inside, Last) in reverse. First, find the two Last terms that will multiply to produce 56 as well and sum (Inside, Outside) to equal 15. For this problem, those two numbers are 7 and 8. Then, plug these into a set of binomials using the square root of the First variable (y²):

y² + 15y + 56
y² + (7 + 8)y + (7 x 8)
(y + 7)(y + 8)

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(2 + 9)(3)
a = ½(11)(3)
a = ½(33) = \( \frac{33}{2} \)
a = 16\(\frac{1}{2}\)