Question

Solve the following equations
3m = 2(m - 3)^2

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Answer 1

First of all, let's expand the square on the right hand side:

`3m=2(m^2-6m+9)`

Distribute the two on the right hand side:

`3m=2m^2-12m+18`

Subtract 3m from both sides:

`0=2m^2-15m+18`

Use the quadratic formula to solve:

`m_(1,2)=(15\pm√(225-144))/(4)=(15\pm 9)/(4)`

So, the solutions are

`m_1=(15+9)/(4)=(24)/(4)=6`

`m_2=(15-9)/(4)=(6)/(4)=(3)/(2)`

Answer 2

m = 6 or m = 3/2

Explanation:

Solve for m over the real numbers:

3 m = 2 (m - 3)^2

Expand out terms of the right hand side:

3 m = 2 m^2 - 12 m + 18

Subtract 2 m^2 - 12 m + 18 from both sides:

-2 m^2 + 15 m - 18 = 0

The left hand side factors into a product with three terms:

-(m - 6) (2 m - 3) = 0

Multiply both sides by -1:

(m - 6) (2 m - 3) = 0

Split into two equations:

m - 6 = 0 or 2 m - 3 = 0

Add 6 to both sides:

m = 6 or 2 m - 3 = 0

Add 3 to both sides:

m = 6 or 2 m = 3

Divide both sides by 2:

Answer: m = 6 or m = 3/2