Please help, having trouble with geometry word problems. Tysm if you do :)
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Hi!
So let's start with some variables.
w is width
L is length.
The length is 4 less than 5 times the width. Let's put that into an equation.
L = 5w - 4
The perimeter is 76.
The perimeter is L + L + w + w or
perimeter = 2L + 2w.
Which means that 1/2 of the perimeter = L + w.
We know the perimeter is 76, so half of 76 is 38.
38 = L + W.
Let's put length in terms of width and plug in the previous equation.
38 = 5w - 4 + w
Add the same variables
38 = 6w - 4
simplify
42 = 6w
w = 7
And plug that into the length equation that we had above to get
L = 35 - 4
L = 31
The correct answer is C: 7, 31
Answer:
1. C. 7, 31 cm
2. A. 43°, 137°
Step-by-step explanation:
1.
A. 14+14+66+66=160 (incorrect)
B. 7+7+27+27= 68 (incorrect)
C. 7+7+31+31= 76 (correct)
D. 7+7+39+39= 92 (incorrect)
For this question, they give you a red herring. Since it's a multiple choice question, you can just add their length and width and see if they add up to 76. Only C. 7, 31 cm dimensions add up to have a perimeter of 76.
2.
Supplementary angles add up to 180°
The formula is x° × 5 = y° × 2 - 59
A. 43° × 5 = 137° × 2 - 59 (correct)
B. 41° × 5 ≠ 139° × 2 - 59 (incorrect)
C. 39° × 5 ≠ 141° × 2 - 59 (incorrect)
D. 37° × 5 ≠ 143° × 2 - 59 (incorrect)
For this question, you can't add up the angle measurements because they all equal 180°. Since it's a multiple choice question, you can just try them and see which one fits. Only A. 43°, 137° has angles that fit our formula.