How do you solve #x^2-x=90#?

Answer 1

#x=10,-9#

On the left, we have what appears to be a quadratic, so we can set it equal to zero to find its roots.

We can subtract #90# from both sides to get
#x^2-x-90=0#

To factor this business on the left, let's do a little thought experiment:

What two numbers sum up to #-1# (coefficient on #x# term) and have a product of #-90# (constant term)?
After some trial and error, we arrive at #-10# and #9#. Thus, our quadratic can be factored as
#(x-10)(x+9)=0#

To solve from here, we can use the Zero Product Property. If the product of two things is equal to zero, one or both of those things must be equal to zero.

Let's set both of them equal to zero to get

#x=10# and #x=-9#

Hope this helps!

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Answer 2

#x=-9#

#x=10#

Solve meaning factor:

#x^2-x=90#
#x^2-x-90=0#

Find 2 numbers such that their sum is -1 and their product is 90:

#a+b=-1# and #a*b=90#
#a=9, b=-10#
#x^2-x-90=0#
#(x+9)(x-10)=0#
#x+9=0#
#x=-9#
#x-10=0#
#x=10#
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Answer 3

To solve the equation ( x^2 - x = 90 ), rearrange it to form a quadratic equation in standard form ( ax^2 + bx + c = 0 ), where ( a = 1 ), ( b = -1 ), and ( c = -90 ). Then, apply the quadratic formula:

[ x = \frac{{-b \pm \sqrt{{b^2 - 4ac}}}}{{2a}} ]

Substitute the values of ( a ), ( b ), and ( c ) into the quadratic formula and solve for ( x ).

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Answer from HIX Tutor

When evaluating a one-sided limit, you need to be careful when a quantity is approaching zero since its sign is different depending on which way it is approaching zero from. Let us look at some examples.

When evaluating a one-sided limit, you need to be careful when a quantity is approaching zero since its sign is different depending on which way it is approaching zero from. Let us look at some examples.

When evaluating a one-sided limit, you need to be careful when a quantity is approaching zero since its sign is different depending on which way it is approaching zero from. Let us look at some examples.

When evaluating a one-sided limit, you need to be careful when a quantity is approaching zero since its sign is different depending on which way it is approaching zero from. Let us look at some examples.

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