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.
Answer:
-2-2√3, -2+2√3
Step-by-step explanation:
Let x represent one of the numbers. Then the other number is -4-x. We want the product to be -8:
x(-4-x) = -8
-4x -x^2 = -8 . . . . . eliminate parentheses
x^2 +4x = 8 . . . . . . multiply by -1
x^2 +4x +4 = 12 . . . add 4 to complete the square
(x +2)^2 = 12
x +2 = ±√12 = ±2√3
x = -2±2√3
The two numbers are -2-2√3 ≈ -5.4641, and -2+2√3 ≈ 1.4641.
Answer:
L = 295ft
W = 95ft
Step-by-step explanation:
Perimeter of a rectangle = 2(L+W)
If the length is 200 ft more than the width, then:
L = 200+W
Substitute
P = 2(200+W+W)
780 = 2(200+2W)
780 = 400+4W
4W = 780-400
4w = 380
W = 380/4
W = 95ft
Since L = 200+w
L = 200+95
L = 295ft
9+3 ←commutative property of 3+9
