11) 3(x-5) + 2(x -1)
distributive multiplication: 3x - 15 + 2x - 2
group like terms : 3x + 2x - 15 - 2
Simplify: 5x - 17
12) arrow is from -3 going towards the right side, meaning greater value. since the circle above -3 is hollow it means that it is not included or not equal.
x > -3
13) 3x + 2y : x = -3 ; y = -4
substitute x and y by its values : 3(-3) + 2(-4) ⇒ -9 - 8 = -17
14) f(n) = -1 + 3(n-1) :
-1 is the first term ; 3 is the common difference ; n is the term you are searching for.
example: n = 4
f(4) = -1 + 3 (4-1) ⇒ f(4) = -1 + 3(3) ⇒ f(4) = -1 + 9 ⇒ f(4) = 8
8 is the fourth term in the sequence.
15) y = 3x² + 4 ; x = -2
y = 3(-2²) + 4
y = 3(4) + 4
y = 12 + 4
y = 16