110k views
1 vote
I need help solving this:
x- √(2x-7) = 5

User MandisaW
by
5.3k points

2 Answers

2 votes

Hope this helps :).

I need help solving this: x- √(2x-7) = 5-example-1
I need help solving this: x- √(2x-7) = 5-example-2
I need help solving this: x- √(2x-7) = 5-example-3
User RafaelTSCS
by
5.4k points
6 votes

I am hoping this was explained well enough:

Step 1 :

Isolate the square root on the left hand side :

Radical already isolated

√2x-7 = 5-x

Step 2 :

Eliminate the radical on the left hand side :

Raise both sides to the second power

(√2x-7)2 = (5-x)2

After squaring

2x-7 = x2-10x+25

Step 3 :

Solve the quadratic equation :

Rearranged equation

x2 - 12x + 32 = 0

This equation has two rational roots:

{x1, x2}={8, 4}

Step 4 :

Check that the first solution is correct :

Original equation

√2x-7 = 5-x

Plug in 8 for x

√2•(8)-7 = 5-(8)

Simplify

√9 = -3

Solution does not check

3 ≠ -3

Step 5 :

Check that the second solution is correct :

Original equation

√2x-7 = 5-x

Plug in 4 for x

√2•(4)-7 = 5-(4)

Simplify

√1 = 1

Solution checks !!

Solution is:

x = 4

One solution was found :

x = 4


User B Seven
by
5.9k points
Welcome to QAmmunity.org, where you can ask questions and receive answers from other members of our community.