2 years ago

I need help with algebra

Mathematics

1 answer:

rosijanka [135]2 years ago

4 0

Answer:

x = -1 and y = 6

Step-by-step explanation:

using x = -b/2a

x = -4 / 2(2)

x = -1

y = 2(-1)² + 4(-1) + 8

y = 2 - 4 + 8

y = 10 - 4

y = 6

You might be interested in

7.21 repeating as a fraction

GalinKa [24]

Answer: 721/100 is 7.21 as a simplified fraction.

3 0

3 years ago

Read 2 more answers

Which is the equation of a line that has a slope of and passes through point (–3, –1)?

Leno4ka [110]

There's no slope, so it's impossible to answer your question. I'm sorry.

3 0

3 years ago

Convert the Cartesian equation (x 2 + y 2)2 = 4(x 2 - y 2) to a polar equation.

SashulF [63]

ANSWER

${r}^{2} = 4 \cos2\theta$

EXPLANATION

The Cartesian equation is

${( {x}^{2} + {y}^{2} )}^{2} = 4( {x}^{2} - {y}^{2} )$

We substitute

$x = r \cos( \theta)$

$y = r \sin( \theta)$

and

${x}^{2} + {y}^{2} = {r}^{2}$

This implies that

${( {r}^{2} )}^{2} = 4(( { r \cos\theta) }^{2} - {(r \sin\theta) }^{2} )$

Let us evaluate the exponents to get:

${r}^{4} = 4({ {r}^{2} \cos^{2}\theta } - {r}^{2} \sin^{2}\theta)$

Factor the RHS to get:

${r}^{4} = 4{r}^{2} ({ \cos^{2}\theta } - \sin^{2}\theta)$

Divide through by r²

${r}^{2} = 4 ({ \cos^{2}\theta } - \sin^{2}\theta)$

Apply the double angle identity

$\cos^{2}\theta -\sin^{2}\theta= \cos(2 \theta)$

The polar equation then becomes:

${r}^{2} = 4 \cos2\theta$

7 0

3 years ago

A circle has radius 50 cm. Which number would be close to the area

ale4655 [162]

Answer:

look do is gone eat

Step-by-step explanation:

7 0

3 years ago

Y=x???need answers and an explanation

Lesechka [4]

Y= 2
every time y goes up it goes up by 2

-1+2=1
1+2=3
3+2=5

5 0

3 years ago