The plus sign means that we have to sum all the terms inside of the second parenthesis, while the minus sign means that we have to change all the signs inside the last parenthesis:
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Now we only have to gather all like terms:
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Answer:
15
Step-by-step explanation:
Let x represent the number of algebra problems. Then the number of geometry problems was 27-x and the total working time was ...
2x +5(27 -x) = 90
-3x = 90 -135 . . . . subtract 135
x = -45/-3 = 15 . . . divide by -3
Rob had 15 algebra problems for homework.
Answer:
x=11
Step-by-step explanation:
Since the lines in the middle are parallel, we know that both sides are proportional to each other.
6:48 can be simplified to 1:8
Since we know the left side ratio is 1:8, we need to match the right side with the same ratio
We can multiply the ratio by 5 to match 5:3x+7
5:40
5:3x+7
Now we can set up the equation: 40=3x+7
Subtract 7 from both sides
3x=33
x=11
GOING ACROSS
First: 2/4
Second: 5/6
Third: 5/6
Fourth: 2/4
Fifth: other
Answer:
Step-by-step explanation: