B) -8 + (-12)
Because you just have to use the distributive property and distribute -1 to (8+12)
Solve for d:
(3 (a + x))/b = 2 d - 3 c
(3 (a + x))/b = 2 d - 3 c is equivalent to 2 d - 3 c = (3 (a + x))/b:
2 d - 3 c = (3 (a + x))/b
Add 3 c to both sides:
2 d = 3 c + (3 (a + x))/b
Divide both sides by 2:
Answer: d = (3 c)/2 + (3 (a + x))/(2 b)
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Solve for x:
(3 (a + x))/b = 2 d - 3 c
Multiply both sides by b/3:
a + x = (2 b d)/3 - b c
Subtract a from both sides:
Answer: x = (2 b d)/3 + (-a - b c)
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Solve for b:
(3 (a + x))/b = 2 d - 3 c
Take the reciprocal of both sides:
b/(3 (a + x)) = 1/(2 d - 3 c)
Multiply both sides by 3 (a + x):
Answer: b = (3 (a + x))/(2 d - 3 c)
Answer:
The Radius is 6.5 cm.
Step-by-step explanation:
We know that the diameter of a circle is a line that begins on one point of a circle and ends on the opposite side. We also know that the radius is a point on the circle that starts from that point and ends at the center. Therefore, the radius would be half the diameter.

Hope this helped :D!