The way that you explained it, you have 8x12 => 96 sq. ft. of red roses. The total area will be twice that, 192 sq. ft. Which means that the new plot would be 12x16, with a two foot border around the original plot.
Of course, you are going to need to use variables in 10th grade.
Let x be the width of the yellow border (it isn't stated, but the border needs to be equal all around, or there are infinite solutions). Drawing it, you will see 8 basic segments, 2 widths, 2 lengths, 4 corners (you can divvy up the segments differently). The area of the yellow bed is the result of all of those areas added together:
2w*x+2l*x + 4x^2 = 96
40x + 4x^2 = 96
0 = x^2 + 10x - 24
0 = (x+12)(x- 2)
checking each factor, and solving for zero, {x = -12} isn't a real answer, so x = 2.
Of course, you are going to need to use variables in 10th grade.
Let x be the width of the yellow border (it isn't stated, but the border needs to be equal all around, or there are infinite solutions). Drawing it, you will see 8 basic segments, 2 widths, 2 lengths, 4 corners (you can divvy up the segments differently). The area of the yellow bed is the result of all of those areas added together:
2w*x+2l*x + 4x^2 = 96
40x + 4x^2 = 96
0 = x^2 + 10x - 24
0 = (x+12)(x- 2)
checking each factor, and solving for zero, {x = -12} isn't a real answer, so x = 2.
Last edited by:
oldandslow: Sep 12, 17 19:47