Answer:
The answer is 27
Step-by-step explanation:
The reason being, you can solve this 2 ways.
1) Combine like terms, 7a-4a = 3a.
Now just substitute (a=9) into 3a.
3 * (9) = 27.
2) Or just substitute a = 9 into the original expression.
7 * (9) - 4 * (9)
= 63 - 36 = 27
Let's simplify step-by-step.<span><span><span><span>5<span>x2</span></span>−<span>3x</span></span>−2</span>−<span>(<span><span><span>−<span>2<span>x2</span></span></span>−x</span>+10</span>)</span></span>Distribute the Negative Sign:<span>=<span><span><span><span>5<span>x2</span></span>−<span>3x</span></span>−2</span>+<span><span>−1</span><span>(<span><span><span>−<span>2<span>x2</span></span></span>−x</span>+10</span>)</span></span></span></span><span>=<span><span><span><span><span><span><span><span>5<span>x2</span></span>+</span>−<span>3x</span></span>+</span>−2</span>+<span><span>−1</span><span>(<span>−<span>2<span>x2</span></span></span>)</span></span></span>+<span><span>−1</span><span>(<span>−x</span>)</span></span></span>+<span><span>(<span>−1</span>)</span><span>(10)</span></span></span></span><span>=<span><span><span><span><span><span><span><span><span>5<span>x2</span></span>+</span>−<span>3x</span></span>+</span>−2</span>+<span>2<span>x2</span></span></span>+x</span>+</span>−10</span></span>Combine Like Terms:<span>=<span><span><span><span><span><span>5<span>x2</span></span>+<span>−<span>3x</span></span></span>+<span>−2</span></span>+<span>2<span>x2</span></span></span>+x</span>+<span>−10</span></span></span><span>=<span><span><span>(<span><span>5<span>x2</span></span>+<span>2<span>x2</span></span></span>)</span>+<span>(<span><span>−<span>3x</span></span>+x</span>)</span></span>+<span>(<span><span>−2</span>+<span>−10</span></span>)</span></span></span><span>=<span><span><span>7<span>x2</span></span>+<span>−<span>2x</span></span></span>+<span>−12</span></span></span>Answer:<span>=<span><span><span>7<span>x2</span></span>−<span>2x</span></span>−<span>12</span></span></span>
452.16 = 3.1416 r^2
r^2 = 452.16 / 3.1416
r^2 = 143.93
r = 11.997
C = 2 (3.1416) (12) =75.38 m
Answer:
Step-by-step explanation:
Answer:
Step-by-step explanation:
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