When three times a number is decreased by five the square root of the result is 7. Find the number

Question

I need help on this word problems for my test so please answer asap thank you all for trying 

Answer 1

sqr(3x-5)=7 square both sides

3x-5 = 49

3x =54

x = 18

Answer 2

sqrt(3x-5) = 7

 

3x - 5 = 49

 

3x = 54

 

x = 18

Answer 3

On this one my friend, all we need to do is convert english to algebra and solve.

 

Let x be the number in question.   Then

 

sqrt(3x - 5) = 7  (The square root of 3 times a number decreased by five is equal to 7).  Solve for x

 

Square both sides:            3x - 5 = 49

Add 5 to both sides:          3x      = 54

Divide by 3 on both sides:   x      = 18

 

Now plug 18 back in to your original word problem.

 

When 3 times a number is decreased by 5  (3 * 18 - 5 = 49) the square root of the result (49) is 7.

 

True enough.

 

Time to slay more dragons my friend.

 

Cheers