Check whether the two expressions 2x+3y2x+3y and 2y+3x2y+3x equivalent.
The first expression is the sum of 2x2x 's and 3y3y 's whereas the second one is the sum of 3x3x 's and 2y2y 's.
Let us evaluate the expressions for some values of xx and yy . Take x=0x=0 and y=1y=1 .
2(0)+3(1)=0+3=32(1)+3(0)=2+0=22(0)+3(1)=0+3=32(1)+3(0)=2+0=2
So, there is at least one pair of values of the variables for which the two expressions are not the same.
The length of the fifth piece is 2 3/4 inches.
Given:
1st piece of wood = 1 1/2 inches
2nd piece of wood = 1 13/16 inches
3rd piece of wood = 2 1/8 inches
f(n) = 1st term + common difference(n-1)
To get the common difference, we need to deduct the fraction from its preceding fraction.
1st piece: 1 1/2 = (2*1 + 1)/2 = 3/2
2nd piece: 1 13/16 = (16*1+13)/16 = 29/16
3rd piece: 2 1/8 = (8*2+1)/8 = 17/8
29/16 - 3/2 = 29/16 - (3/2 * 8/8) = 29/16 - 24/16 = (29-24)/16 = 5/16
17/8 - 29/16 = (17/8 *2/2) - 29/16 = 34/16 - 29/16 = (34-29)/16 = 5/16
Find: 5th piece's measurement
1st term : 1 1/2 or 3/2
common difference : 5/16
f(5) = 3/2 + 5/16 (5-1)
= 3/2 + 5/16 (4)
= 3/2 + (5*4)/16
= 3/2 + 20/16
= (3/2 * 8/8) + 20/16
= 24/16 + 20/16
= (24 + 20)/16
f(5) = 44/16
f(5) = 2 12/16 simplified to 2 3/4 inches.
