Step-by-step explanation:
∠A + ∠B + ∠C = 180°
Here the value of ∠B and C is given below...we need to find the value of ∠A ....
a + 120° + 40° = 180°
a + 160° = 180°
a = 160° - 180°
a = 20°

Answer:
x = {-1/5, 1}
Step-by-step explanation:
(5x - 2)² - 1 = 8
Add 1 to both sides
(5x - 2)² = 9
Take the square root of both sides
5x - 2 = ±3
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<u>Solution I</u> for 5x - 2 = +3
5x - 2 = 3
add 2 to both sides
5x = 5
Divide both sides by 5
x = 1
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<u>Solution II</u> for 5x - 2 = -3
5x - 2 = -3
add 2 to both sides
5x = -1
Divide both sides by 5
x = -1/5
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x = {-1/5, 1}
2x + 3y = 45
x + y = 10......y = 10 - x
2x + 3(10 - x) = 45
2x + 30 - 3x = 45
-x + 30 = 45
-x = 45 - 30
-x = 15
x = -15 <====
and y = 25
Look at the coefficient of x (the slope).
Is -2 positive or negative?
Since -2 is negative, The slope is negative.