Solve the system of equations using the substitution method. 2x+8y=4 x=−3y+5

1 answer:

7 0

Since x=-3y+5, substitute x for -3y+5.

2(-3y+5)+8y=4

Distribute.

-6y+10+8y= 4

2y+10= 4

Subtract 10 on both sides.

2y=-6

Divide by 2.

y=-3

Plug in y=-3.

x=-3(-3)+5
x= 9+5
x=14

(14,-3)

We can check this.

2(14)+8(-3)=4
28-24=4
4=4 <== this works

I hope this helps!
~kaikers

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two trains leave stations 210 miles apart at the same time and travel tword each other. one train at 85 miles per hour while the

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recall your d = rt, distance = rate * time.

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they are 210 miles apart and moving toward each other, at some point they will meet, when that happens, the faster train A has covered say d miles, and the slower B has covered then the slack from 210 and d, namely 210 - d.

When both trains meet, A has covered more miles than B because A is faster, however the time both have been moving, is the same, say t hours.

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