Answer:
ABD=180 and EHF=90
Step-by-step explanation:
Answer:
option 1 is true. -1/2=-0.5
Answer: A; 6.3%
Step-by-step explanation:
Problem 1
For the first problem, we first want to find y so that we can plug it into the expression.
We can use elimination method for the system of equations to solve.
3x+3y=21
3x-y=5
We subtract both equations to eliminate x.
4y=16 [divide both sides by 4]
y=4
Now that we know y, we can plug it into the expression.
[divide]
[subtract]

We know that the answer is A.
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Problem 2
For the second problem, we need to know how to calculate percent error. The formula for precent error is
. We know that the exact value is 80 because the buyer was supposed to given 80. 75 is the measured value because that was what the buyer was given.
[subtract]
[solve absolue value]
[divide]
[multiply]

Since the problem said to round to one decimal place, we know that the answer is 6.3%.
Answer:
Step-by-step explanation:
error in measurement = 480 - 469 = 11 inches
Percent error = error *100/actual length
= 11 * 100 /480 = 2.9%
<h2>
Height of tree is 7.5 feet</h2>
Step-by-step explanation:
Let t be the height of pole.
Given that the tree is 5 feet shorter than a pole.
Height of pole = t + 15
Also given that the pole is 3 times as tall as the tree.
Height of pole = 3t
So we have
t + 15 = 3t
2t = 15
t = 7.5 feet
Height of tree = 7.5 feet