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3 years ago

6

35 points + brainliest!

1 answer:

jarptica [38.1K]3 years ago

8 0

Answer:

x= -2-√11. or. x= -2 + √11

Step-by-step explanation:

solving quadratic equation by completing the square

x^2+4x-7=0

x^2+4x=7

x^2+4x + (4/2)^2=7 + (4/2)^2 ( adding (1/2 coefficient of x)^2 on both sides

x^2+4x + 4=7 + 4

x^2+4x + 4=11. factorize(x^2+4x + 4) into (x + 2)^2

(x + 2)^2=11

√(x + 2)^2= + - √11

x + 2 = + - √11

there are two different solution .

x + 2 = -√11. or x + 2 = + √11.

x= -2-√11. or. x= -2 + √11.

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X - 1 > -3 add 1 to both sides:-

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and

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2 years ago

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Answer:

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Step-by-step explanation:

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2 years ago

Which number line represtents the solution to |x+4|=2?

vlada-n [284]

Answer:

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Step-by-step explanation:

Use the definition of absolute value as a starting point

$|x|=x\,\,\mbox{for}\,\,x\geq 0\\|x|=-x\,\,\mbox{for}\,\,x$

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7 0

2 years ago

Given: m∠EYL=72°<br> Find: mEHL , mLVE

White raven [17]

Answer:

Part 1) The measure of arc EHL is $108\°$

Part 2) The measure of angle LVE is $54\°$

Step-by-step explanation:

step 1

Let

x-----> the measure of arc EHL

y----> the measure of arc EVL

we know that

The measurement of the outer angle is the semi-difference of the arcs it encompasses.

so

$m$

we have

$m$

substitute

$72\°=\frac{1}{2}(y-x)$

$144\°=(y-x)$

$y=144\°+x$ ------> equation A

Remember that

$x+y=360\°$ -----> equation B ( complete circle)

substitute equation A in equation B and solve for x

$x+(144\°+x)=360\°$

$2x=360\°-144\°$

$x=216\°/2=108\°$

Find the value of y

$y=144\°+x$

$y=144\°+108\°=252\°$

therefore

The measure of arc EHL is $108\°$

The measure of arc EVL is $252\°$

step 2

Find the measure of angle LVE

we know that

The inscribed angle measures half that of the arc comprising

Let

x-----> the measure of arc EHL

$m$

we have

$x=108\°$

substitute

$m$

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