Knowing y kx b, when x 1, y 2 when x 1, y 4, find the values of k and b.

When x=1, y=2; When x -1, y = -4

Substituting y=kx+b, we get, 2=k+b, -4=-k+b

solution, k = 3, b = -1

What's the problem? Have you thought about it?!

Doesn't bringing in the values of x and y respectively to form a binary equation?

Then, according to the solution of the binary equation, the values of k and b can be obtained.

Specifically, count yourself, you can't be so lazy!

Dude, you're in the second year of junior high school! Math is terrible! I'm also in the second year of junior high school, I'm good at math, really, I'll help you!

Since y=kx+b, the values of x and y are added to the function.

2=k+b and 4=-k+b

Use the steps to solve the equation to find the values of k and b.

Both k=3, b=-1

x=1, y=2; When x -1, y=-4 is substituted into the analytic formula.

Get the system of equations.

k+b=2k-b=-2

Solve it. k=3

b=-1, so y=3x-1

Substituting the x and y values into the equation yields.

2=1*k+b……①4=-1*k+b……-2=2b, i.e., b=-1

Substituting b=-1 into , we get 2=1*k+(-1), i.e., k=3

From the meaning of the question, we can see that k+b=2, -k+b=-4 solves the system of equations composed of these two equations, and the values of these two letters can be obtained. k=3,b=-1.

When x=1, y=1 kx+b=k+b=1 When x=2, Qina y=4kx+b=2k+b=4 - Vertical header to get k=3, substitute k=3 into b=-2 k=3, b=-2, and you can ask if you don't understand.

Hope for the aftermath.

When x=1, y=1; When x=2, y=-4

Then 1=k+b

4=2k+b②

Get k = -5

Substituting , the solution is b=6

y=kx+b, when x=1, y=1; When x=2, y=4.

Description k*1+b=1

k*2+b=4

The solution gives k=3 b=-2

Substituting the known conditions into y=kx+b, we get two formulas, k+b=1, 2k+b=-4, solve the equation to get k=-5, b=6, oh, choose c

Just substitute x=1, y=2 and x=4, y=-4 into the equation respectively, and you can get 2 equations about k and b, and solve them.

The solution yields k = -2 and b = 4

Solution: Knowing from the meaning of the question.

When x=1 y=2 so 2=k+b (1)x=4, y=-4 so -4=4k+b (2) solve the equation.

k=-2 b=4

When x=,y=2 times are entered.

2=k+b when x=4, y=-4 are entered.

4=4k+b

2=k+b that makes up the system of equations

4=4k+b

k=-2, b=4 (only two equations are required to subtract when solving the system of equations).

Just go in for it.

When x=1.

2=k+b①

When x=4.

4=4k+b②

k= 2 b=4 is obtained by the elimination element of ,

Substituting x,y into the analytic formula y=kx+b gives the system of equations {k+b=2; 4k+b=4;Solve the equation: Equation 1 - 2 to get -3k = -2, solve k = 2 3, substitute k = 2 3 into equation 1, solve x = 3 4Or cut off a formula with 2 formulas, process:

3k=2, k=2 3, x=3 4And is your y -4? If so, the first two are correct.

Solution: y=kx+b, when x=1, y=1;When x=2, y=-4, substituting gets: {k+b=1 2k+b=-4 , gets:k=-5, substitute k=-5 into gets: -5+b=1, b=6, i.e. {k=-5b=6

Therefore, C

put x=1, y=2; x=-1,y=0 points, don't bring y=kx+b socks into the equation system, and solve it to destroy the wheel.

2=k=b （1）

0=-k+b （2）

1) + (2) yields: 2=2b

b=1 brings b=1 into (1).

2=k+1k=1

Solution: Substituting x=1 y=4 into y=kx+b, there is k+b=4 Eq. 1

Substituting x=2 y=10 into y=kx+b There are 2k+b=10 Eq. 2 is subtracted from Eq. 1 to get k-2k=4-10

The solution is k=6

Substituting Eq. 1, we get 6+b=4 and we get b=-2

i.e. k=6 b=-2 is what is sought.