Use ac method
for ax²+bx+c=0 when a≠1
multiply a and c, let's call the product r
what 2 numbesr multiply to get r and add to get b
2y²+9y+9=0
2*9=18
wat 2 numbers multiply to get 18 and add to get 9
3 and 6
split it up to that
2y²+3y+6y+9=0
group
(2y²+3y)+(6y+9)=0
factor
y(2y+3)+3(2y+3)=0
undistribute
(y+3)(2y+3)=0
set to zero
y+3=0
y=-3
2y+3=0
2y=-3
y=-3/2
y=-3 and -3/2
it's factored form is (x+3)(2x+3)
It is systematic because they are going every tenth person
Answer:
x=11.2426
or
x=2.7574
Step-by-step explanation:
9514 1404 393
Answer:
Step-by-step explanation:
If we let x and y represent the costs of a lamp and end table, respectively, the two purchases can be written as ...
3x +2y = 520
2x -y = 20
__
These equations can be solved many ways. If we use "elimination", we can add twice the second equation to the first to eliminate y:
(3x +2y) +2(2x -y) = (520) +2(20)
7x = 560 . . . . simplify
x = 80 . . . . . . divide by 7
y = 2x -20 = 2(80) -20 = 140
The cost of a lamp is $80; the cost of an end table is $140.
