81
(-9)(-9) is 81
Multiplying two negatives gives a positive
Answer:
18.0 (use 18 if 18.0 is not an answer choice)
Step-by-step explanation:
15²+10²=225+100 = 325
√325 = 18.028 or 18.0 (use 18 if 18.0 is not an answer choice)
Answer:
6
Step-by-step explanation:
x = area to be painted
y = gallons of paint needed
we know already one point of that function/graph :
x = 800
y = 2
so, for a simple relationship between the 2 variables we can assume
y = ax
2 = a×800
a = 2/800 = 1/400
so, we get
y = (1/400) x
for 2400 ft²
y = 1/400 × 2400 = 1/4 × 24 = 24/4 = 6
she needs 6 gallons of paint for 2400 ft².
Simplifying x2 + -8x = 20 Reorder the terms: -8x + x2 = 20 Solving -8x + x2 = 20 Solving for variable 'x'. Reorder the terms: -20 + -8x + x2 = 20 + -20 Combine like terms: 20 + -20 = 0 -20 + -8x + x2 = 0 Factor a trinomial. (-2 + -1x)(10 + -1x) = 0 Subproblem 1Set the factor '(-2 + -1x)' equal to zero and attempt to solve: Simplifying -2 + -1x = 0 Solving -2 + -1x = 0 Move all terms containing x to the left, all other terms to the right. Add '2' to each side of the equation. -2 + 2 + -1x = 0 + 2 Combine like terms: -2 + 2 = 0 0 + -1x = 0 + 2 -1x = 0 + 2 Combine like terms: 0 + 2 = 2 -1x = 2 Divide each side by '-1'. x = -2 Simplifying x = -2 Subproblem 2Set the factor '(10 + -1x)' equal to zero and attempt to solve: Simplifying 10 + -1x = 0 Solving 10 + -1x = 0 Move all terms containing x to the left, all other terms to the right. Add '-10' to each side of the equation. 10 + -10 + -1x = 0 + -10 Combine like terms: 10 + -10 = 0 0 + -1x = 0 + -10 -1x = 0 + -10 Combine like terms: 0 + -10 = -10 -1x = -10 Divide each side by '-1'. x = 10 Simplifying x = 10Solutionx = {-2, 10}