Here is one way to solve for x.

Step 1) 2x^2-7=9

Step 2) 2x^2-7+7=9+7

Step 3) 2x^2=16

Step 4) (2x^2)/2=16/2

Step 5) x^2=8

Step 6) sqrt(x^2)=sqrt(8)

Step 7) |x|=sqrt(8)

Step 8) x=sqrt(8) or x=-sqrt(8)

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Below are explanations/reasons to each of the steps above.

Step 1) Original equation

Step 2) Add 7 to both sides

Step 3) Combine like terms

Step 4) Divide both sides by 2

Step 5) Simplify

Step 6) Apply the square root to both sides. The notation "sqrt" is shorthand for "square root"

Step 7) Use the rule that sqrt(x^2) = |x| for all real numbers x

Step 8) Use the rule that if |x| = k then x = k or x = -k for some fixed number k.

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The two solutions are
x = sqrt(8) or x = -sqrt(8)

3 0

3 years ago

Consider a right triangle that has these dimensions: the side opposite angle a is 6 meters and the side adjacent angle a is 8 me

Varvara68 [4.7K]

To determine the length of the hypotenuse, we need a relation that would relate the other legs and the hypotenuse of the triangle. So, we would need to use the Pythagorean theorem which is an equation that relates the hypotenuse with the other legs of a right triangle. It is to be noted that this is only usable for right triangles only. It is expressed as follows:

c^2 = a^2 + b^2

where c is the hypotenuse and a, b are the other legs.

c = √(a^2 + b^2)
c = √(6^2 + 8^2)
c = √100
c = 10 m

Therefore, the length of the hypotenuse with the other legs having a length of 6 and 8 would be 10 m.

5 0

3 years ago

Is 100 in greater than 3yd 1ft

wolverine [178]

1 yard = 36 inches

3 * 36 = 108

1 foot = 12 inches

108 + 12 = 120

So 3 yards and 1 foot is equal to 120 inches.

120 is greater than 100 so 3 yards and 1 foot is greater than 100 inches.

3 0

3 years ago

Read 2 more answers

I ready scientific notation help

Airida [17]

The required value is $2\times10^9$

Step-by-step explanation:

Weight of ants = $4\times10^{-3}$

Weight of elephant= $8\times10^6$

We need to find, the total weight of about how many ants equals to the weight of an oversized elephant.

The equation given is:

$4\times10^{-3} \times a = 8\times10^6$

We need to find a:

Solving:

$4\times10^{-3} \times a = 8\times10^6\\a=\frac{8\times10^6}{4\times10^{-3}}\\if \,\,10^a/10^-b \,\,then\,\, 10^{a+b}\\a=2\times10^{6+3} \\a=2\times10^9$

So, the required value is $2\times10^9$

Keywords: Scientific Notation

Learn more about Scientific Notation at:

#learnwithBrainly

4 0

2 years ago