A right angle measures 90 degrees and is the intersection of two perpendicular lines. In diagrams, a right angle is indicated by a small box completing a square with the perpendicular lines.

To solve this equation, isolate the variable for which you are solving (c) on one side of the equation and put everything else on the other side.

c + 4z = 7c + 6z - 9
c = 7c + 6z - 9 - 4z
c - 7c = 6z - 9 - 4z
-6c = 2z - 9
c = \( \frac{2z - 9}{-6} \)
c = \( \frac{2z}{-6} \) + \( \frac{-9}{-6} \)
c = -\(\frac{1}{3}\)z + 1\(\frac{1}{2}\)

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

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.

7a³ + 9a³ = 16a³

The sum of the interior angles of a triangle is 180°:
180° = a° + b° + c°
c° = 180° - a° - b°
c° = 180° - 51° - 20° = 109°