To multiply binomials, use the FOIL method. FOIL stands for First, Outside, Inside, Last and refers to the position of each term in the parentheses:

(y - 1)(y + 2)
(y x y) + (y x 2) + (-1 x y) + (-1 x 2)
y² + 2y - y - 2
y² + y - 2

An exterior angle of a triangle is equal to the sum of the two interior angles that are opposite:

d° = b° + c°

To find angle c, remember that the sum of the interior angles of a triangle is 180°:

180° = a° + b° + c°
c° = 180° - a° - b°
c° = 180° - 29° - 55° = 96°

So, d° = 55° + 96° = 151°

A shortcut to get this answer is to remember that angles around a line add up to 180°:

a° + d° = 180°
d° = 180° - a°
d° = 180° - 29° = 151°

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

-4b + x = 1
x = 1 + 4b

then substitute the result (1 - -4b) into the second equation:

5b + 7(1 + 4b) = 2
5b + (7 x 1) + (7 x 4b) = 2
5b + 7 + 28b = 2
5b + 28b = 2 - 7
33b = -5
b = \( \frac{-5}{33} \)
b = -\(\frac{5}{33}\)

The surface area of a cylinder is 2πr² + 2πrh:

sa = 2πr² + 2πrh
sa = 2π(5²) + 2π(5 x 7)
sa = 2π(25) + 2π(35)
sa = (2 x 25)π + (2 x 35)π
sa = 50π + 70π
sa = 120π

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.

2a - 8a = -6a