The equation of the area of a triangle is Area=Length×Width. We know area=256.5 and length is 18. So now we know 256.5=18×width. We then divide 256.5÷18 to get the width. The width is 14.25. Perimeter=legth+length+width+width. If width is 18 and length is 14.25 then we add up all 4 sides. 18+18+14.25+14.25=64.5. 64.5 is the perimeter
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x + 2x + 9y - 7y
3x + ( 9y - 7y )
3x + 2y
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To find the mean you first add all the numbers up you get each day
12+16+0+8+31+28+17=112
Than you divided it by how many days there are...
112/7=16
So the mean is 16
If you are charging 5 per hour use h to determine how many hours and add 10 for the connection fee
5h+10