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

-3b + y = 3
y = 3 + 3b

then substitute the result (3 - -3b) into the second equation:

3b - 9(3 + 3b) = 6
3b + (-9 x 3) + (-9 x 3b) = 6
3b - 27 - 27b = 6
3b - 27b = 6 + 27
-24b = 33
b = \( \frac{33}{-24} \)
b = -1\(\frac{3}{8}\)

The volume of a cylinder is πr²h:

v = πr²h
v = π(3² x 4)
v = 36π

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.

4a - 7a = -3a

A rectangle is a parallelogram containing four right angles. Opposite sides (a = c, b = d) are equal and the perimeter is the sum of the lengths of all sides (a + b + c + d) or, comonly, 2 x length x width. The area of a rectangle is length x width. A square is a rectangle with four equal length sides. The perimeter of a square is 4 x length of one side (4s) and the area is the length of one side squared (s²).

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.

(5a)(4ab) + (7a²)(6b)
(5 x 4)(a x a x b) + (7 x 6)(a² x b)
(20)(a¹⁺¹ x b) + (42)(a²b)
20a²b + 42a²b
62a²b