Answer:
d. 188.4 in
Step-by-step explanation:
i might be wrong so sorry in advance.
x = number of 1-cent stamps
y = number of 8-cent stamps
z = number of 12-cent stamps
We have 31 stamps all together, so x+y+z = 31.
"I have 4 more 1-cent stamps than 8-cent stamps" means we have the equation x = y+8. Whatever y is, add 8 to it to get x. Solve for y to get y = x-8.
You also have "twice as many one cent stamps as 12 cent stamps", so x = 2z. Solving for z gets you z = 0.5x
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x+y+z = 31
x+x-8+z = 31 ... y replaced with x-8
x+x-8+0.5x = 31 ... plug in z = 0.5x
2.5x-8 = 31
2.5x = 31+8
2.5x = 39
x = 39/2.5
x = 15.6
Your teacher made a typo somewhere because we should get a positive whole number result for x (since x is a count of how many 1-cent stamps we have).
i think the answer is the second choice √9+√9=2√9
<em>Hoped this helped!</em>
4x+5 = 8x - 11
4x - 8x = -11 - 5
-4x = -16
x = 4
4x+5 = 4(4) +5 = 21
8x - 11 = 8(4) - 11 = 21
<RST = 21 + 21 = 42
answer
<RST = 42 degrees
