Answer:
First brand = 18 gallons
Second brand = 12 gallons
Step-by-step explanation:
Let the first brand brand be A and the second brand be B.
Thus, since he wants to obtain 30 gallons of a mixture that contains 30% pure antifreeze, then we have;
A + B = 30 - - - (eq 1)
Also; The first brand is 20% pure antifreeze, and the second brand is 45% pure antifreeze. Thus;
0.2A + 0.45B = (0.3 × 30)
0.2A + 0.45B = 9 - - - (eq 2)
From eq 1, we have; A = 30 - B
Put 30 - B for A in eq 2;
0.2(30 - B) + 0.45B = 9
6 - 0.2B + 0.45B = 9
0.25B = 9 - 6
0.25B = 3
B = 3/0.25
B = 12
Thus, A = 30 - 12 = 18 gallons
Commutative means 'you can swap them'. I.e., a+b = b+a, addition is commutative. Subtraction is not.
The first answer: <span>2(6a − 3) = (6a − 3) ⋅ 2 is an example where 2 and (6a-3) are the factors that can be swapped, because multiplication is commutative.</span>
Answer:
63.4°
Step-by-step explanation:
Given that AB and BC are the legs of the right triangle, then opposite to angle A is side BC and adjacent to angle A is side AB.
By definition, the tangent of angle A is:
tan(∠A) = opposite leg / adjacent leg
tan(∠A) = BC/AB
tan(∠A) = 12/6
∠A = arctan(2)
∠A = 63.4°
3(-4+8) distribute the 3 to -4 and 8
(-12 + 24) add the terms
12
