8-5=-3 It's negative 3 because the 8 is greater than 5
20: 30-4 x (2+5)=2
21. 17-(8-5)= 14
22. You put (10/2)-3+1, but it isn't necessary
Explanation: to solve these equations, use PEMDAS (parentheses, exponents, multiplication, division.) these equations don't involve exponents, though, so ignore that part. If 30 is left alone, you would multiply 4x2 before doing anything else. This would mean you would have 30-8+5' which gets you to 27, an incorrect answer. However, if you put parentheses around (2+5), you add those first, meaning you would then have 30-4(2+5) = 30-4(7) = 30-28= 2.
Try to do the rest; if you're still having trouble add a comment
Answer:
c = -54
Step-by-step explanation:
Solve for c:
(7 c)/8 - 3 (c/8 - 7) = -6
Put each term in c/8 - 7 over the common denominator 8: c/8 - 7 = c/8 - 56/8:
(7 c)/8 - 3 c/8 - 56/8 = -6
c/8 - 56/8 = (c - 56)/8:
(7 c)/8 - 3(c - 56)/8 = -6
(7 c)/8 - (3 (c - 56))/8 = (7 c - 3 (c - 56))/8:
(7 c - 3 (c - 56))/8 = -6
-3 (c - 56) = 168 - 3 c:
(7 c + 168 - 3 c)/8 = -6
7 c - 3 c = 4 c:
(4 c + 168)/8 = -6
Multiply both sides of (4 c + 168)/8 = -6 by 8:
(8 (4 c + 168))/8 = -6×8
(8 (4 c + 168))/8 = 8/8×(4 c + 168) = 4 c + 168:
4 c + 168 = -6×8
8 (-6) = -48:
4 c + 168 = -48
Subtract 168 from both sides:
4 c + (168 - 168) = -168 - 48
168 - 168 = 0:
4 c = -168 - 48
-168 - 48 = -216:
4 c = -216
Divide both sides of 4 c = -216 by 4:
(4 c)/4 = (-216)/4
4/4 = 1:
c = (-216)/4
The gcd of -216 and 4 is 4, so (-216)/4 = (4 (-54))/(4×1) = 4/4×-54 = -54:
Answer: c = -54
$56, trust me I took Calc. this is easy compared to that
