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.

4a x 8b = (4 x 8) (a x b) = 32ab

You need to find the value of c so solve the first equation in terms of y:

-9c + y = -6
y = -6 + 9c

then substitute the result (-6 - -9c) into the second equation:

-8c + 5(-6 + 9c) = -6
-8c + (5 x -6) + (5 x 9c) = -6
-8c - 30 + 45c = -6
-8c + 45c = -6 + 30
37c = 24
c = \( \frac{24}{37} \)
c = \(\frac{24}{37}\)

A line on the coordinate grid can be defined by a slope-intercept equation: y = mx + b. For a given value of x, the value of y can be determined given the slope (m) and y-intercept (b) of the line. The slope of a line is change in y over change in x, \({\Delta y \over \Delta x}\), and the y-intercept is the y-coordinate where the line crosses the vertical y-axis.

When solving an equation with two variables, replace the variables with the values given and then solve the now variable-free equation. (Remember order of operations, PEMDAS, Parentheses, Exponents, Multiplication/Division, Addition/Subtraction.)

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.

-z + 4 = 1 - 2z
-z = 1 - 2z - 4
-z + 2z = 1 - 4
z = -3