Step-by-step explanation:
1) first eliminate constant(number without variable) you eliminate constant by doing the inverse operation(if constant is being added, then subtract)(if constant is being subtracted, then add it)
ex: if x+9=32
subtract 9 from both sides to get rid of it
x=23
2) if there is another constant but this constant is being multiplied/divided then do the opposite operation to remove it
you could multiply by 3 on both sides:
x+9=69
x=60
Answer:
12
Step-by-step explanation:
substitute b = 3 and c = 4 into the expression
8b - 3c
= 8(3) - 3(4)
= 24 - 12
= 12
Everyone should do this derivation, because otherwise the "quadratic formula" is some sort of "magic" LOL...
ax^2+bx+c=0
x^2+bx/a+c/a=0
x^2+bx/a=-c/a
x^2+bx/a+b^2x/(4a^2)=b^2/(4a^2)-c/a
(x+b/(2a))^2=(b^2-4ac)/(4a^2)
x+b/(2a)=±√(b^2-4ac)/(2a)
x=-b/(2a)±√(b^2-4ac)/(2a)
x=(-b±√b^2-4ac)/(2a)
Answer:
Solution: (-4,5)
Step-by-step explanation:
x=16-4y
3x+4y=8
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The 1st equation tells you x = 16-4y
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Substitute that into the 2nd equation
and solve for "y":
3(16-4y)+4y = 8
48 - 12y + 4y = 8
-8y = -40
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y = 5
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Solve for "x"
x = 16-4y
x = 16-4*5
x = 16-20
x = -4
Answer is 7pi (you had my explanation earlier)