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3 years ago

Find the vertex of the parabola whose equation is y = -2x2 + 8x - 5.

1 answer:

3 0

Hello :
y = -2x² + 8x - 5 = -2(x²-4x-5)
but : x²-4x = (x²-4x +2²)-2²
= (x-2)² -4
y = -2 ((x-2)²-9)
y = -2 (x-2)²+18
the vertex is A(2,18)

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Lnx=-3

scZoUnD [109]

Answer:

because It's rounded to the nearest hundred place

Step-by-step explanation:

Given equation:

$\ln(x ) = - 3$

recall that,

$\ln(a ) = b \iff {e}^{b} = a$

remember, In is natural logarithm which is actually nothing but common logarithm with the base euler's number (e) . anyway rewriting lnx=-3 yields:

$\ln( x ) = - 3\\ \iff {e}^{ - 3} = \frac{1}{ {e}^{3} }$

1/e³ is approximately 0.0497870684..... , rounding it to the nearest hundred place would be 0.05 which is the same answer as your textbook .

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2 years ago

Do the sides 9, 12 and 15 make a right triangle?

Fynjy0 [20]

Answer:

YES

Step-by-step explanation:

because they are all different lengths

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3 years ago

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What are the coordinates of the pre-image of N' if it was reflected across the y-axis, and N' has coordinates (3, -1)?

kirill115 [55]

I believe it is (-3,-1)

5 0

3 years ago

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Can anyone solve this question??? plss plsss its my request to all if any one can solve this question I will mark him/ her the b

almond37 [142]

Answer:

a) ∠EAB = 180° - 90° - 30° = 60°

∠EBA = 180° - 90° - 60° = 30°

a) ∠EBA = 30°

b) ∠DCA = 180° - 90° - 30° = 60°

∠EBA ≅ ∠DAC, ∠EAB ≅ ∠DCA, ∠AEB ≅ ∠CDA

ΔEBA ≅ ΔDAC because of the AAA postulate

c) EB ≅ DA, EA ≅ DC, AB ≅ CA

d) AB = CA given

sin ∠EAB = EB/AB (sin 60°) EB = (0.8660)AB

cos ∠EAB = EA/AB (cos 60°) EA = (0.5)AB

cos ∠DAC = AD/CA (cos 30°) AD = (0.8660)CA

sin ∠DAC = CD/CA (sin 30°) CD = (0.5)CA

ED = EA + AD

ED = (0.5)AB + (0.8660)CA

since AB = CA, ED = 1.366CA

since EB = (0.8660)AB and AB = CA, then EB = 0.866CA

since CD = 0.5CA,

EB + CD = 0.866CA + 0.5CA = 1.366CA

EB + CD = 1.366CA

1.366CA = 1.366CA

Proof: ED = EB + CD

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3 years ago

How many solutions does 2x+2-3x=3x-4

DerKrebs [107]

Answer:

1 solution (x = 1.5)

Step-by-step explanation:

2x + 2 - 3x = 3x - 4

First, combine like terms

2 - x = 3x - 4

Add 4 to both sides

6 - x = 3x

Add x to both sides

6 = 4x

Divide both sides by 4

1.5 = x

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