To solve this equation, repeatedly do the same thing to both sides of the equation until the variable is isolated on one side of the equal sign and the answer on the other.

-7x - 8 = \( \frac{x}{1} \)
1 x (-7x - 8) = x
(1 x -7x) + (1 x -8) = x
-7x - 8 = x
-7x - 8 - x = 0
-7x - x = 8
-8x = 8
x = \( \frac{8}{-8} \)
x = -1

To find the diagonal we need to know the length of one of the square's sides. We know the area and the area of a square is the length of one side squared:

a = s²

so the length of one side of the square is:

s = \( \sqrt{a} \) = \( \sqrt{4} \) = 2

The Pythagorean theorem defines the square of the hypotenuse (diagonal) of a triangle with a right angle as the sum of the squares of the other two sides:

c² = a² + b²
c² = 2² + 2²
c² = 8
c = \( \sqrt{8} \) = \( \sqrt{4 x 2} \) = \( \sqrt{4} \) \( \sqrt{2} \)
c = 2\( \sqrt{2} \)

The perimeter of a triangle is the sum of the lengths of its sides:

p = x + y + z
p = 7cm + 10cm + 11cm = 28cm

The first step to solve a quadratic equation that's set to zero is to factor the quadratic equation:

x² + 5x + 6 = 0
(x + 2)(x + 3) = 0

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

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

So the solution is that x = -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.

8a + 4a = 12a