Answer:
I don't know sorry
sorry
Step-by-step explanation:
I don't know sorry
sorry
Answer:
Step-by-step explanation:
<h2>4/x=2/10</h2>
cross multiplication:
4*10=2*x
40=2x
x=40/2=20
<h2>w/2 = 4.5/6.8</h2>
6.8w=2(4.5)
6.8w=9
w=9/6.8=1.32352941
Answer: 70.1
Step-by-step explanation:
Step-by-step explanation:
log <base a> b = x
means
a^x = b
So
3^2 = x^2+7x+21
x^2 + 7x + 21 - 9 = 0
x^2 + 7x + 12 = 0
(x+3)(x+4)
x = -3 or -4
Here is one way to solve for x.
Step 1) 2x^2-7=9
Step 2) 2x^2-7+7=9+7
Step 3) 2x^2=16
Step 4) (2x^2)/2=16/2
Step 5) x^2=8
Step 6) sqrt(x^2)=sqrt(8)
Step 7) |x|=sqrt(8)
Step 8) x=sqrt(8) or x=-sqrt(8)
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Below are explanations/reasons to each of the steps above.
Step 1) Original equation
Step 2) Add 7 to both sides
Step 3) Combine like terms
Step 4) Divide both sides by 2
Step 5) Simplify
Step 6) Apply the square root to both sides. The notation "sqrt" is shorthand for "square root"
Step 7) Use the rule that sqrt(x^2) = |x| for all real numbers x
Step 8) Use the rule that if |x| = k then x = k or x = -k for some fixed number k.
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The two solutions are
x = sqrt(8) or x = -sqrt(8)