<h3>
Answer:</h3>
42. 29°
43. 3x³ +2x² -3x +10
44. 20a² +68a
<h3>
Step-by-step explanation:</h3>
42. The right-angle corner tells you the two marked angles are complementary — they sum to 90°.
(-3x +20)° + (-2x +55)° = 90°
-5x +75 = 90 . . . . . . . . . . collect terms, divide by °
-5x = 15 . . . . . . . . . . . . . . . subtract 75
x = -3 . . . . . divide by the coefficient of x
The angle of interest is (-3x+20)°. Filling in the found value for x, we have ...
(-3·(-3) +20)° = 29° = m∠BDC
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43. The distributive property is useful for multiplying polynomials.
(x +2)(3x² -4x +5) = x(3x² -4x +5) +2(3x² -4x +5)
= 3x³ -4x² +5x +6x² -8x +10 . . . . . eliminate parentheses
= 3x³ +2x² -3x +10
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44. Area is the product of length and width, so this becomes a problem in multiplying polynomials.
area = (5a +17)(4a) = 20a² +68a . . . . area in square feet
First you plug in the variables:
(-3)(2)+(6)(-3)(4)
Multiply:
-6+(-18)(4)
-6+-72
Add and your answer comes out to be:
-78
Answer:
q = 3 + 1/2r
Step-by-step explanation:
10q - 5r = 30
We want to solve for q
Add 5r to each side
10q - 5r+5r = 30+5r
10q = 30+5r
Divide by 10
10q/10 = 30/10 +5r/10
q = 3 + 1/2r
