Answer:
7(3a + 5)
Step-by-step explanation:
Rewrite 21 as 7 · 3
Rewrite 35 as 7 · 5
Therefore,
⇒ 21a + 35 = 7 · 3a + 7 · 5
Factor out common term 7:
⇒ 7 · 3a + 7 · 5 = 7(3a + 5)
Answer:
150 mL
Step-by-step explanation:
Let x represent the quantity of 75% solution needed. The total amount of alcohol in the 60% mixture will be ...
75%·x + 10%·45 = 60%·(x+45) . . . . . there will be x+45 mL of solution in the end
0.15x = 22.5 . . . . . . . . . . . . . . . . . . . . simplify, subtract .60x+4.5
22.5/0.15 = x = 150 . . . . . . . . . . . . . . mL of 75% solution needed
You will need 150 mL of the 75% solution.
Answer:
D
Step-by-step explanation:
2 Answers: Choice B and Choice C
The rate of change is 2.
The rate of change is constant.
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Explanation:
The first point on the left is when x = 1.5 and it has a height of y = 1
The point (1.5, 1) is on the line.
So is the point (3,4) for similar reasoning.
Compute the slope between those points
m = (y2-y1)/(x2-x1)
m = (4-1)/(3-1.5)
m = 3/(1.5)
m = 2
The slope is 2, which is the same as saying the rate of change is 2. This only applies when x > 1 of which the interval 1.5 ≤ x ≤ 3 is a part of.
Since the slope stays at 2 on the interval 1.5 ≤ x ≤ 3, this means we consider the slope to be constant. If the curve bended at all on this interval, then it wouldn't be a constant slope.
Check picture for working out
