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2 years ago

What values of x would make the following equation true?

Mathematics

2 answers:

bixtya [17]2 years ago

8 0

There are many ways to do this. Such ways are using the quadratic formula, completing the square, etc.
We have $x^2+10x-21=0$ We can add 46 to both sides so the -21 becomes a +25. by doing that, we get $x^2+10x+25=46$ This can be wrote as $(x+5)^2=46$ We solve the square root and get $(x+5)= +-\sqrt{46}$ (The +- is a plus minus sign.) Subtract five on both sides to get $x=-5+- \sqrt{46}$
The answer is C.

zlopas [31]2 years ago

8 0

There are many ways to do this. Such ways are using the quadratic formula, completing the square, etc.

We have We can add 46 to both sides so the -21 becomes a +25. by doing that, we get This can be wrote as We solve the square root and get (The +- is a plus minus sign.) Subtract five on both sides to get

The answer is C.

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Scrat [10]

Answer:

A 3x10^-6

Step-by-step explanation:

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2 years ago

Write an equation for a circle with a diameter that has endpoints at (7, –4) and (1, –10). Round to the nearest tenth if necessa

Black_prince [1.1K]

The standard form for the equation of a circle is :

(x−h)^2+(y−k)^2=r2 ----------- EQ(1)
where handk are the x and y coordinates of the center of the circle and r is the radius.
The center of the circle is the midpoint of the diameter.

So the midpoint of the diameter with endpoints at (7,-4)and(1,-10) is :

((7+(1))/2,(-4+(-10))/2)=(4,-7)

So the point (4,-7) is the center of the circle.

Now, use the distance formula to find the radius of the circle:

r^2=(7−(4))^2+(-4−(-7))^2=9+9=18

⇒r=√18

Subtituting h=4, k=-7 and r=√18 into EQ(1) gives :

(x-4)^2+(y+7)^2=18

7 0

2 years ago

Elmer walked 5.4 miles every day. How far did he walk in 11 days?

AURORKA [14]

Answer:

59.4

Step-by-step explanation:

8 0

2 years ago

Read 2 more answers

Tuto

Damm [24]

Answer:

8r+8pg-pq

Step-by-step explanation:

The subtractable pg cancels out one of the 9 pg's. So 9 pg-1 pg= 8 pg

Hope this helps!

8 0

2 years ago

Rewrite the expression $6j^2 - 4j 12$ in the form $c(j p)^2 q$, where $c$, $p$, and $q$ are constants. What is $\frac{q}{p}$

solniwko [45]

$Rewrite the expression 6j^2 - 4j + 12$ in the form $c(j + p)^2 + q$, where $c$, $p$, and $q$ are constants. What is $\frac{q}{p}$$

The ratio of $\frac{q}{p}$ = - 34

How to solve such questions?

Such Questions can be easily solved just by some Algebraic manipulations and simplifications. We just try to make our expression in the form which question asks us. This is the best method to solve such questions as it will definitely lead us to correct answers. One such method is completing the square method.

Completing the square is a method that is used for converting a quadratic expression of the form $ax^{2} + bx + c$ to the vertex form

$a(x - h)^{2} + k$ . The most common application of completing the square is in solving a quadratic equation. This can be done by rearranging the expression obtained after completing the square: $a(x + m)^{2} + n$ , such that the left side is a perfect square trinomial