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).

You need to find the value of b so solve the first equation in terms of z:

-9b + z = 6
z = 6 + 9b

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

-3b + 6(6 + 9b) = 4
-3b + (6 x 6) + (6 x 9b) = 4
-3b + 36 + 54b = 4
-3b + 54b = 4 - 36
51b = -32
b = \( \frac{-32}{51} \)
b = -\(\frac{32}{51}\)

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

z² + 15z + 54 = 0
(z + 6)(z + 9) = 0

For this expression to be true, the left side of the expression must equal zero. Therefore, either (z + 6) or (z + 9) must equal zero:

If (z + 6) = 0, z must equal -6
If (z + 9) = 0, z must equal -9

So the solution is that z = -6 or -9

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