2x2-35=15 Solve using the square root property?

2008-07-09 2:50 pm
. Solve using the square root property:
2x2 – 35 = 15

回答 (8)

2008-07-09 2:58 pm
✔ 最佳答案
2x^2 - 35 = 15
2x^2 = 15 + 35
2x^2 = 50
x^2 = 50 / 2
x^2 = 25
then we take the square root of both sides
x = +5 and -5
2008-07-09 9:57 pm
absoltely agree with first guy
2008-07-09 10:06 pm
When you have a problem like this:
2x² - 35 = 15

The first thing you do is try to separate as many numbers from x as is possible.

In math, the general rule in solving an equation is that whatever you do to one side you do to the other as well so I'm going to add 35 to both sides to make it disappear on one side:

2x² - 35 + 35 = 15 + 35
which gives:
2x² = 50

In my quest to separate x from all numbers I will now divide both sides by 2:

2x²/2= 50/2
which gives:

x² = 25

I will now find the square root of both sides:

√x² = √25

x = +5 or - 5
(a lot of people are tempted to just write down 5 but you have to remember that -5 * -5 is also 25)
2008-07-09 10:03 pm
2x² - 35 = 15
2x² = 50
x² = 25
by using the square root property, we will get the square root of both sides.
x = ±5
but the principal root is +5. :D
2008-07-09 10:02 pm
first answerer got it right
2008-07-09 9:58 pm
2x^2=35+15=50
orx^2=25=5^2
or x=+5 or -5
2008-07-09 9:57 pm
2x^2 - 35 = 15
2x^2 = 15 + 35
2x^2 = 50
x^2 = 50/2
x^2 = 25
x = ±√25
x = ±5
2008-07-09 9:54 pm
2x² - 35 = 15
2x² = 50
x² = 25
x = ±5


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