The area of a triangle is equal to ½ base x height:

a = ½bh
a = ½ x 3 x 4 = \( \frac{12}{2} \) = 6

The area of a rectangle is equal to its length x width:

a = l x w
a = a x b
a = 6 x 2
a = 12

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:

b² + 3b - 1 = 2b + 5
b² + 3b - 1 - 5 = 2b
b² + 3b - 2b - 6 = 0
b² + b - 6 = 0

Next, factor the quadratic equation:

b² + b - 6 = 0
(b - 2)(b + 3) = 0

For this expression to be true, the left side of the expression must equal zero. Therefore, either (b - 2) or (b + 3) must equal zero:

If (b - 2) = 0, b must equal 2
If (b + 3) = 0, b must equal -3

So the solution is that b = 2 or -3

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.

8a⁴ + 5a⁴ = 13a⁴

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 -4 as well and sum (Inside, Outside) to equal 0. For this problem, those two numbers are -2 and 2. Then, plug these into a set of binomials using the square root of the First variable (y²):

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