Answers:

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Work Shown:


P = perimeter

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A = area

Answer:
Step-by-step explanation:
"one half the sum of a number and 4" is (1/2)(n + 4)
"three less than the quotient of 5 and the number" is 5/n - 3
putting this all together, we get
(1/2)(n + 4) = (5/n) - 3
<span>2/5 is close to 1/2, and it is easy to find 1/2 of 7 mentally. Half of 7 is 3.5, so Martin gave away about 3.5 pounds.</span>
Answer:
Step-by-step explanation:
1) Two angles supplementary. So sum of two angles is 180
One angle = x
Other angle = 2x
x + 2x = 180
3x = 180
x = 180/3 = 60
The angles are 60, 120
2)Two angles complementary. So sum of two angles is 90
one angle = x
Other angle = x + 20
x +x +20 = 90
2x + 20 = 90
2x = 90- 20
2x = 70
x = 70/2 = 35
The angles are 35,55
3) one angle =x
Other angle = 3x - 20
x + 3x - 20 = 120
4x = 120 + 20
4x = 140
x = 140/4 = 35
The angles are 35,85
5) x + 4x -20 = 180
5x = 180 + 20
5x = 200
x = 200/5 = 40
x = 40
6) This sum is not clear only half is visible