Question 667047
let length =x
width  y

2(x+y) = perimeter

2(x+y)=228
x+y=114...................(1)

7x+4y=690.................(2)

multiply equation (1) by -4
we get -4x-4y=-456
add this equation to (2)
3x= 234
/3
x= 78 the length

plug x in (1)
x+y=114
78+y=114
y=114-78
y=36 the width