-4x-2y=-10 3x+y=4 Using substitution

Mathematics

1 answer:

Citrus2011 [14]3 years ago

3 0

Let get x from the first equation

-4x=+2y-10

x=-1/2y + 5/2

Now substitute the x in the second equation

3(-1/2y+5/2)+y=4

-3/2y + 15/2 + y =4

Move the terms without the y to the other side

-3/2y + y = -15/2 +4

Now multiple both side by 2

-3y +2y = -15+8

-y = -7

Y = 7 (ANSWER)

Now we substitute the y in the first equation so we can get the x

x = -1/2 (7) + 5/2

x = -7/2 + 5/2

x = -2/2

X = -1 (SECOND ANSWER)

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sergey [27]

Since it is a geometric sequence each term will be a specific multiple of the term preceding it, called the common ratio...

126/42=378/126=1134/378=3

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8 0

3 years ago

I don't even know how to figure this out. I don't have a formula for this

yuradex [85]

Answer:

$\sin\theta=\dfrac{15}{17}$

$?=15$

Step-by-step explanation:

Use the trigonometry formula

$\cos^2\theta+\sin^2\theta=1$

You are given that

$\cos \theta=\dfrac{8}{17}$

Substitute into the first formula

$\left(\dfrac{8}{17}\right)^2+\sin^2\theta=1\\ \\\dfrac{64}{289}+\sin^2\theta=1\\ \\\sin^2\theta=1-\dfrac{64}{289}=\dfrac{289-64}{289}=\dfrac{225}{289}\\ \\\sin \theta=\pm \dfrac{15}{17}$