Easey
ratio and proprotion
or
knowlege
1. ratio and proportion
distance/time=2/30
2hours=60*2=120mins
xdistance
2/30=x/120
1/15=x/120
times boht sides by 120
120/15=x
8=x
8 miles
knowlege way
30 mins=1/2 hour
30 mins=1/4 of 2 hours
2=1/4 of 2 hours
2*4=8
8 miles
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)
I believe that it is 24.99 but I'm not too sure. Anyways I hope I helped!
I think it would be the 3rd one if not im sorry i tried
Answer:
33
Step-by-step explanation:
7x3=21
4x3=12
21+12=33
