A room is 10.2 m long, 8.5 m wide and 4.6 m high. It has a door measuring 1.5 m x 2.6 m and a window measuring 2 m x 1.7 m. Find the cost of tiling the walls at the rate of 13.50 per sqm

You move the constant to the right side and change its sign to be 9z= -6 -8. that’s the first step.the second step would be calculate the difference of -8-6 to get -14. you equation should now be 9z=-14the last step is to divide both sides by 9 to get z=-14/9hope this

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