Answer:
The answer is D.
Step-by-step explanation:
We have to apply Discriminant Law. When a quadratic equation, ax² + bx + c = 0 has equal roots so the discriminant will be 0. Then, you have to substitute the values into the formula :








-6 it is just the opposite of the number. So a positive would be a negative and a negative a positive. So the answer to your question is -6.
Answer:
m<ABC = 45
m<DBC = 34°
Step-by-step explanation:
Given:
m<ABD = 79°
m<ABC = (8x - 3)°
m<DBC = (5x + 4)°
Step 1: Generate an equation to find the value of x
m<ABC + m<DBC = m<ABD (angle addition postulate)
(8x - 3) + (5x + 4) = 79
Solve for x
8x - 3 + 5x + 4 = 79
13x + 1 = 79
Subtract 1 from both sides
13x + 1 - 1 = 79 - 1
13x = 78
Divide both sides by 13
x = 6
Step 2: find m<ABC and m<DBC by plugging the value of x into the expression of each angle
m<ABC = (8x - 3)°
m<ABC = 8(6) - 3 = 48 - 3 = 45°
m<DBC = (5x + 4)°
m<DBC = 5(6) + 4 = 30 + 4 = 34°
Step-by-step explanation:
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