30
juan solves the system of equations by forming a matrix equation.

−4x+y=9
3x+2y=7

he multiplies the left side of the coefficient matrix by the inverse matrix.

how does he proceed to the solution?

  multiply the left side of the constant vector by the inverse matrix

Step-by-step explanation:

The matrix equation ...

  AX = B

is solved by left-multiplying by the inverse of A:

  A⁻¹AX = A⁻¹B

  IX = A⁻¹B . . . . . the result of multiplying A⁻¹A is the identity matrix

  X = A⁻¹B . . . . . B needs to be multiplied by the inverse matrix

step-by-step explanation:

let

we know that

the y-intercept is the y-coordinate of the point when the value of x is equal to zero

so

the y-coordinate of the point a is the y-intercept

the answer part a) is

the value of y-intercept is

part b) find the slope m

we know that

the value of the slope is equal to

substitute the values

therefore

the answer part b) is

the value of the slope is equal to

the general answer is

the slope is

the value of y-intercept is