2x+y=18. What is x and what is y ?

Question

Please help me solve this as my math is rusty after all these years of non-use. Thank you.

Answer 1

x = 0

2x + y = 18

2(0) + y = 18

0 + y = 18

y = 18

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When x = 0 , y = 18

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y = 0

2x + y = 18

2x + 0 = 19

2x = 18

2x / 2 = 19/ 2

x = 18/2

x = 9

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When y = 0 , x = 9

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Answer 2

Well, first what you want to do is get the variables on either side of the equals, so divide both sides by 2x and you'll have something like y = 18/2x, then what you need to do is invert the 18/2x so that 2x is the numerator, so multiply by 2x/2x then you'll have y = 36x/2x^2, this ensure that your answer in the denominator can't be negative since the x is squared. Since you now have x in the numerator and denominator you can cancel the X's, and you have y = 36/2^2, which is 36/4, which is 9. so with y = 9 you can just plug it into the original equation, and you get 2x +9 = 18, so divide by 9 on both sides, you get 2x = 2 and then divide by 2, and you get x = 1. so y = 9, x = 1

Answer 3

hi..
2x+y=18...
This can be considered as an equation of a line. it is a linear equation which means that the powers of x and y are 1.
the slope 'm' can be calculated as y=-2x+18. Here maintaining the coefficient of y as 1 we get the coefficient of x as -2 which gives us the slope of the line.

so if you want to plot this line on the graph x and y can hold different values.

2x+y=18
for x=1 y=16
x=2 y=14
x=3 y=12
x=4 y=10
x=-5 y=28

and so on...therefore x and y can hold any number of values.

Answer 4

You need to put this equation by slope-intercept form:
y=mx+b

Subtract 2x from both sides:
y=-2x+18

All you need to do is replace x with numbers in order to get the y-values. Here are some examples:

x=0
y=-2(0)+18
y=18
(0,18)

y=0
-2x+18=0
-2x=-18
x=9
(9,0)

x=1
y=-2(1)+18
y=-2+18
y=16
(1,16)

x=2
y=-2(2)+18
y=-4+18
y=14
(2,14)

x=3
y=-2(3)+18
y=-6+18
y=12
(3,12)

I hope this helps!

Answer 5

2(8)+2=18

Answer 6

Answering as asked:

You have two unknowns and only one relationship between them, so there is an indefinite number of solutions for x and y, but within a fixed range.

This range of points, values of x and y, both positive and negative, lie along a straight line with gradient -2 and which cut through points (0, 18) and (9, 0) on the y and x axis respectively; , e.g. (-2,22);(-4,26); (0, 18); (1,16); 2,14); (3,12)....etc.

Answer 7

X and y could be many values. You need another equation or limiting factor.

if x = 1 than y = 16
if x = 2 than y = 14
if x = 3.7283 than y = 10.5434

What you have now is the equation for a line, and that line shows the infinite number of solutions.

Answer 8

You cannot determine x and y with just one equation.

If you have 2 unknowns (variables) you must have at least 2 equations in order to solve for unique solutions.

Answer 9

2x+y=18
y = 18 - 2x
let x = 1
:. y = 16

Answer 10

two unknowns can not be found with only one equation.You have to give either x or y a value in order to solve this problem.