Split - Quadratic equations

cphilpott777 said:
my problem is (x - 1)^2=49 how do you get the exact solution

49 = 7[sup:ky3mvo71]2[/sup:ky3mvo71]

If

a[sup:ky3mvo71]2[/sup:ky3mvo71] - b[sup:ky3mvo71]2[/sup:ky3mvo71] = 0 , then

(a + b)(a - b) = 0 ? a + b = 0 ? a = -b

or

a - b = 0 ? a = b

so a = ± b

Follow the exact the same steps.
 
Another approach is to start by taking the square root of both sides.

You know that the square root of 49 is 7.

On the left-hand side, we have the square root of (x - 1)^2.

You need to know that the square root of an algebraic expression squared like (x - 1)^2 is the absolute value of the radicand.

In other words, the square-root of (x - 1)^2 is |x - 1|.

|x - 1| = 7

Now, follow the definition of absolute value, to get rid of the absolute value symbols. Then, finish by solving the two resulting equations in x.
 
Let's do another problem

Solve for 'y' when:

(y + a)[sup:nsqb8d0l]2[/sup:nsqb8d0l] = b[sup:nsqb8d0l]2[/sup:nsqb8d0l]

(y + a)[sup:nsqb8d0l]2[/sup:nsqb8d0l] - b[sup:nsqb8d0l]2[/sup:nsqb8d0l] = 0

[(y + a) + b] [(y + a) - b] = 0

Then by applying 'zero product rule'

we have

[(y + a) + b] = 0

y = - a - b

or

[(y + a) - b] = 0

y = b - a

or we can write

y = -b ± a

put appropriate numbers and you are done!
 
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