To multiply monomials, multiply the coefficients (the numbers that come before the variables) of each term, add the exponents of like variables, and multiply the different variables together.

(7a)(5ab) + (4a²)(4b)
(7 x 5)(a x a x b) + (4 x 4)(a² x b)
(35)(a¹⁺¹ x b) + (16)(a²b)
35a²b + 16a²b
51a²b

You can only add or subtract monomials that have the same variable and the same exponent. For example, 2a + 4a = 6a and 4a² - a² = 3a² but 2a + 4b and 7a - 3b cannot be combined. However, you can multiply and divide monomials with unlike terms. For example, 2a x 6b = 12ab.

A parallelogram is a quadrilateral with two sets of parallel sides. Opposite sides (a = c, b = d) and angles (red = red, blue = blue) are equal. The area of a parallelogram is base x height and the perimeter is the sum of the lengths of all sides (a + b + c + d).

Angles around a line add up to 180°. Angles around a point add up to 360°. When two lines intersect, adjacent angles are supplementary (they add up to 180°) and angles across from either other are vertical (they're equal).

The first step to solve a quadratic expression that's not set to zero is to solve the equation so that it is set to zero:

y² + 3y + 0 = y + 3
y² + 3y + 0 - 3 = y
y² + 3y - y - 3 = 0
y² + 2y - 3 = 0

Next, factor the quadratic equation:

y² + 2y - 3 = 0
(y - 1)(y + 3) = 0

For this expression to be true, the left side of the expression must equal zero. Therefore, either (y - 1) or (y + 3) must equal zero:

If (y - 1) = 0, y must equal 1
If (y + 3) = 0, y must equal -3

So the solution is that y = 1 or -3