To answer your question: Rewrite <span>81<span>x2</span></span> as <span><span>(<span>9x</span>)</span>2</span>.<span><span><span>(<span>9x</span>)</span>2</span><span>−49</span></span>Rewrite 49 as <span>72</span>.<span><span><span>(<span>9x</span>)</span>2</span><span>−<span>72</span></span></span> Both terms are perfect squares, factor using the difference of squares formula, <span><span><span>a2</span><span>−<span>b2</span></span></span>=<span><span>(<span>a+b</span>)</span><span>(<span>a<span>−b</span></span>)</span></span></span> where <span>a=<span>9x</span></span> and <span>b=7</span>.<span><span>(<span><span>9x</span>+7</span>)</span><span>(<span><span>9x</span><span>−7</span></span><span>)</span></span></span>
We have 60 gallons of 20% antifreeze.
How much 70% antifreeze do we add to get 60% antifreeze?
We'll make "x" the gallons of 70% we must add.
.20 * 60 + .70 x = .60 * (60 + x)
12 + .70x = 36 + .60x
.10x = 24
x = 240 gallons of 70% antifreeze.
Source
1728.com/mixture.htm (see example B)
Answer:
c = 24
Step-by-step explanation:
1/3c - 7 = 1
add 7 to both sides
1/3c = 8
now multiply 3 to both sides
c = 24
Answer:
764 US Fluid Ounce
Step-by-step explanation:
Refrence Sheet Used: https://media.studyisland.com/pics/FL8thgradereferencesheet.html
27 US Liquid Quarts = 864 US Fluid Ounces, - 100 US Fluid Ounces = 764
Answer:
Osvoldo did not meet his goal
Step-by-step explanation:
To know the percentage of carbohydrates that Osvoldo ate from grains with respect to the total, we simply have to divide the amount of carbohydrates he got with the grains by the total
55 / 220 = 0.25
then to express it as a percentage this number has to be multiplied by 100
0.25 * 100 = 25%
Osvoldo wanted to reach 30% and only got 25%
25% < 30%