algebra help please?

Question

I need to sole this by using the square root property can anyone show me the way to do it and the step taken to get to the answer? Thanks so very much for your help 2x^2 - 3 = 15

Answer 1

Start by using basic algebra to isolate x^2:

2x^2 - 3 = 15
2x^2 = 18
x^2 = 9

Now you know the value of x^2. If you take the square root of both sides, you get x = sqrt(9) = 3. However, when the original equation contains x^2, there is a second solution and it is the negative square root of the value. Thus, the actual solution is x = 3 or -3.

Answer 2

You have "2x^2-3=15" Your goal of any equation should be to isolate the variable and make it easier to solve for. Add 3 to both sides. You now have "2x^2=18". Divide both sides by 2 and get "x^2=9". By square root property, take square root of both "x^2" and "9". The square root of x^2 is simply x. The square root of 9 is 3. The solutions are 3 and -3.

Answer 3

2x^2 -3 = 15
Add three to both sides:
2x^2 = 15 + 3 = 18
Divide bothe sides by 2:
x^2 = 18/2 = 9
take the square root of both sides:
(x^2)^.5 = (9)^.5
x = 3
There is also a negative root, -3. Either one plugged into the original equation will yield a positive check...
Plug into original equation for the check...

Answer 4

2x^2 - 3 = 15
2x^2 = 18
x^2 = 9
x = 3 or -3

The answer is NECESSARILY +3 and -3 as you can square either one of these to get 9. Later, as you get into applications....Analytic geometry..Graphing polynomials..You will see where this is every relevant and germain.

As with anything else in math..Endeavor to master today's lesson. Doing so will make tomorrow's easier.