Question

Help mi out plz..... solve using matrix method​

Answer 1

x =
`(22)/(7)`

y =
`\frac{3}7}`

Explanation:

`2x-3y=5\\5x=4y=14\\\\\left[\begin{array}{cc}2&-3\\5&-4\\\end{array}\right] \left[\begin{array}{c}x\\y\\\end{array}\right] =\left[\begin{array}{c}5\\14\\\end{array}\right]`

Let A =
`\\\left[\begin{array}{cc}2&-3\\5&-4\\\end{array}\right]`

The inverse of A multiplied by A = the identity matrix
`\left[\begin{array}{cc}1&0\\0&1\\\end{array}\right]`

Inverse of A =
`(1)/(detA)`
`\left[\begin{array}{ccc}-4&3\\-5&2\\\end{array}\right]`

detA = ad - bc =
`-8 - - 15 = 7`

Inverse of A =
`\left[\begin{array}{cc}(-4)/(7) &(3)/(7) \\(-5)/(7) &(2)/(7)\\\end{array}\right]`

`\left[\begin{array}{ccc}x\\y\\\end{array}\right] = \left[\begin{array}{cc}(-4)/(7) &(3)/(7) \\(-5)/(7) &(2)/(7)\\\end{array}\right] \left[\begin{array}{ccc}5\\14\\\end{array}\right] = \left[\begin{array}{ccc}(22)/(7) \\(3)/(7) \\\end{array}\right]`