1. 4b - 2 : the product of 4 and a number (b) decreased by 2
2. the sum of 15 and 4 times a number......15 + 4x
3. 8 fewer boys then girls...how many boys.......b = g - 8
4. It will be less then 1 because of the negative exponent....a negative exponent will mean the number is less then 1...I dont really know how else to explain it.
5. Doug is twice Anna's age...doug is 34 years old
I dont know the 5 step plan...but I am putting what I do know
d = doug's age
a = anna's age
d = 2a
d = 34
34 = 2a
34/2 = a
17 = a....so anna is 17
check..
d = 2a
d = 2(17)
d = 34 (correct)
3x - 3y = -12 ------------- (1)
7x + 2y = -19 --------------(2)
(1) x 2 : 6x - 6y = - 24 ----------- (1a)
(2) x 3 : 21x + 6y = -57 ----------- (2a)
(1a) + (2a) : 27x = - 81
x = - 3
Sub x = -3 into (1) : 3(-3) - 3y = - 12
y = - 12 + 9
y = - 3
Answer( -3, -3)
Cos(38°) = x/44 ⇒ x = 44 * cos(38°) ≈ 34.7 units
<h3>
Answer: C) x = 80</h3>
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Work Shown:
Let's cross multiply to get the following
14/20 = 56/x
14*x = 20*56
14x = 1120
x = 1120/14
x = 80
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As a way to check the answer, we can type 14/20 - 56/80 into the calculator and we should get 0. I'm taking advantage of the rule that if A = B, then A-B = 0. This trick is handy to check if two sides of any equation are equal to one another.
7x - 9 = 28 + 4x - 4
7x - 4x = 28 - 4 + 9
3x = 33
x = 11
