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2 years ago

Solve the system using elimination 4x-7y=3 x-7y=-15

Mathematics

2 answers:

BigorU [14]2 years ago

6 0

The answer is 6,3
.......

ehidna [41]2 years ago

5 0

Answer: x=6 and y=3

Step-by-step explanation:

4x - 7y = 3 -------(1)

x - 7y = -15 ------(2)

equation(1) - equation (2)

3x = 18

Divide bothside by 3

x = 18/3

x= 6

also, multiply equation (2) by 4

4x - 28y = -60--------------(3)

subtract equation(3) from equation(1)

21y = 63

divide bothside by 21

y = 63/21

y = 3

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Given g(x) = -x + 5, solve for x when g(x) = 3.

Elan Coil [88]

Both equal g(x) so put them together

-x+5=3 then solve for x

-x=3-5
-x=-2
-2 divided by -x =2

x=2

5 0

2 years ago

What is the quantity proportional to 18/6

mario62 [17]

Answer:

18/6=3

Step-by-step explanation:

18/6÷3=6/2

6/2=3

7 0

3 years ago

A projectile is launched into the air. The function h(t) = –16t2 + 32t + 128 gives the height, h, in feet, of the projectile t s

Zinaida [17]

Answer:

t = 4 seconds

Step-by-step explanation:

The height of the projectile after it is launched is given by the function :

$h(t)=-16t^2+32t+128$

t is time in seconds

We need to find after how many seconds will the projectile land back on the ground. When it land, h(t)=0

So,

$-16t^2+32t+128=0$

The above is a quadratic equation. It can be solved by the formula as follows :

$t=\dfrac{-b\pm \sqrt{b^2-4ac} }{2a}$

Here, a = -16, b = 32 and c = 128

$t=\dfrac{-32\pm \sqrt{(32)^2-4\times (-16)(128)} }{2\times (-16)}\\\\t=\dfrac{-32+ \sqrt{(32)^2-4\times (-16)(128)} }{2\times (-16)}, \dfrac{-32\- \sqrt{(32)^2-4\times (-16)(128)} }{2\times (-16)}\\\\t=-2\ s\ \text{and}\ 4\ s$

Neglecting negative value, the projectile will land after 4 seconds.

4 0

3 years ago

The ratio of boys to girls in Ella’s grade is 3 to 4. The ratio of boys to girls in Minh’s grade is 4 to 5. Each grade has a tot

Alex_Xolod [135]

Answer:

12 boys

Step-by-step explanation:

I believe the answer is 12 boys. I hope this helps!

8 0

2 years ago

Create a linear equation in the slope-intercept form that contains points (2,−8) and (6,−4) .

nadezda [96]

Answer:

y = x - 10

Step-by-step explanation:

Find the slope:

-4 - (-8) ÷ 6 - 2

-4 + 8 ÷ 6 - 2

4 ÷ 4

= 1

Substitute into the slope-intercept equation:

y = mx + b

Let's use the first coordinate (2,-8) for the x and y values

m = 1

-8 = 1(2) + b

-8 = 2 + b

-2 -2

-10 = b

Write equation:

y = 1x -10 or y = x -10

3 0

2 years ago