I'm not sure but I think it is false.
Roots of the equation 3x² -3x-6=0 are -1 and 2,
all choices are given wrong
3*2²-3*2-6=0
12-6-6=0
0=0, which is true , so root is 2
3*20²-3*20-6=0
600-60-6=0
534=0 which is wrong, so root is 2, but not 20
2x = 3
x = 3/2 or 1 1/2 or 1.5
Answer: 98.1%
Explanation:
A 10% sale means that the post-sale price of the item is now 90%, or 0.9 of the original cost of the item. We then apply 9% sales tax by multiplying the 0.9 by 109%, or 1.09. 0.9 * 1.09 = .981, so the total cost of the item is 98.1% of the original pre-sale sticker price.
For percentage problems that do not deal with a specific starting number, it is always helpful to plug in 100 for the starting number. Here, we would then have a post-sale price of 90 dollars, and if we calculate the sales tax for the 90-dollar item it would be 90 * 0.09 = $8.10. THis gives us a total cost of 90 + 8.10 = $98.10, or 98.1% of the original 100-dollar price.
<span>1. Make y the subject
a) 4y=12x+18
y = 3x + 4.5
b) 2x=7-3y
3y = -2x + 7
y = -2/3x + 7/3
2.
a) what is the equation of the line which passes through both (-2,-4) and (6,16)
slope = (16 + 4)/(6 +2) = 20/8 = 2.5
y = mx + b
-4 =2.5(-2) +b
-4 = -5 +b
b = 1
equation
y = 2.5x + 1
b) what is the equation of the line perpendicular to y= 1/2X + 7 passing through point (3,9)
</span>y= 1/2X + 7
slope = 1/2
slope of line perpendicular = -2
passing through point (3,9)
y = mx + b
9 = -2 (3) + b
b = 15
equation
y = -2x + 15
