First solve for x in the first equation. So you'll have to substitute,
5(3x-7)=20
15x-35=20
Then add 35 to both sides.
15x=55
Divide 55 by 15.
So x = 3.66...
Then plug in 3.7 for x in 6x-8
6(3.7)-8
Its approximately 14.2
Answer:
Step-by-step explanation:
Equation: 82.5 + 2x = 338.5
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2x ÷ _2__ = 256 ÷ _2__
x = _128__
2 students more were introducced in the class and each group had 8 people
Answer:
# red marbles = 25
# blue marbles = 7
Step-by-step explanation:
r + b = 32
r = 4 + 3b
substitute '4 + 3b' for 'r' in the 1st equation
4 + 3b + b = 32
4 + 4b = 32
4b = 28
b = 7
red = 32 - 7
r = 25
Answer:
Step-by-step explanation:
The answer is C