Answer:
(B)
4 +/- 3 sqrt(2) or 4+3sqrt(2) and 4-3sqrt(2)
Step-by-step explanation:
4(c-4)^2=72
4(c-4)(c-4)=72
foil the parenthesis (first, outside, inside, last)
4(c^2 -4c -4c +16)=72
4(c^2-8c+16)=72
divide each side by 4
c^2-8c+16=18
subtract 18 from both sides
c^2-8c-2
use quadratic formula
((-b +/- sqrt((-b^2)-4ac)))/2a
((-(-8)+/-sqrt((-8)^2-4(1)(-2)))/2(1))
(8+/-sqrt(64-(-8)))/2
(8+/-sqrt(64+8))/2
(8+/-sqrt(72))/2
(8+/-sqrt(36 * 2))/2
(8+/-6sqrt(2))/2
4+/-3sqrt(2)
or 4+3sqrt(2) and 4-3sqrt(2)
The slope of the first equation would be -5/2 because
2y=-5x+8
y=-5x/2+4
The y intercept of the 2nd equation is when x=0, so -7y=10
y=-10/7
The equation of the line would be y=-5x/2-10/7
Or in standard form....
5x/2+y=-10/7
5x+27=-20/7
Answer:
(c)=81°, a=9.1, b=12.
Step-by-step explanation:
m<A=40°, m<B=59
m<C=180-(40+59)=81
c=14
A=P×(0.8)
A is the price after the markdown
P is the original price
0.8 is the multiplier because 1-(80/100)=0.8
80/100 is the same as 80%, which is the remaining value when 20% of the value of the item is deducted.
