I need help in learning how to solve this equation using substitution:

Mathematics

1 answer:

Tomtit [17]3 years ago

4 0

Answer:

x=3, z=-1, y=6

Step-by-step explanation:

you need to make the coefficients of each variable equal to each other then subtract 2 equations.

this one: multiply -4 in 1st

4x+4y+4z=32

-4x+4y+5z=7

_____________

8x+0-z=25

we have 2 equations with 2 variables now

2x+2z=4

8x-z=25

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Solve the following system of equations by graphing.

MrMuchimi

Answer:

<h2>Graph b</h2>

Step-by-step explanation:

The equation of a linear function in slope-intercept form:

$y=mx+b$

m - slope

b - y-intercept

The graph of linear function is a straight line therefore we need only two points to the plotting the graph.

$-4x+3y=-12\qquad\text{add 4x to both sides}\\\\3y=4x-12\qquad\text{divide both sides by 3}\\\\y=\dfrac{4}{3}x-4\\\\for\ x=0\to y=\dfrac{4}{3}(0)-4=0-4=-4\to(0,\ -4)\\\\for\ x=3\to y=\dfrac{4}{3}(3)-4=4-4=0\to(3,\ 0)$

$-2x+3y=-18\qquad\text{add 2x to both sides}\\\\3y=2x-18\qquad\text{divide both sides by 3}\\\\y=\dfrac{2}{3}x-6\\\\for\ x=0\to y=\dfrac{2}{3}(0)-6=0-6=-6\to(0,\ -6)\\\\for\ x=3\to y=\dfrac{2}{3}(3)-6=2-6=-4\to(3,\ -4)$

8 0

3 years ago

Cassie has 1/2 pound of sugar in her cabinet. Her cake calls for 2/10 of a pound of sugar. How many cakes can she make?

dmitriy555 [2]

1/2 is also 5/10 so she can make 2 cakes, but really its 2 and a half cakes but u cant make a half

8 0

3 years ago

I need to know how to do a)^

riadik2000 [5.3K]

he charges a fixed cost of $12, meaning a one-time charge of 12 bucks, plus 1.50 for each window.

1 window................ 12 + 1.5(1)

2 windows............. 12 + 1.5(2)

3 windows............. 12 + 1.5(3)

4 windows............. 12 + 1.5(4)

x windows............. 12 + 1.5(x)

$\bf \stackrel{cost}{y}=\stackrel{\stackrel{fixed}{cost}}{12}+\stackrel{\stackrel{per}{window}}{1.5x}$

$\bf \stackrel{cost}{28.50}=\stackrel{\stackrel{fixed}{cost}}{12}+\stackrel{\stackrel{per}{window}}{1.5x}\implies 16.50=1.5x\implies \cfrac{16.50}{1.5}\implies \boxed{11=x}$