The original price of the phone is $137.99. It is now on sale for 1/10 off the original price. This means that the discount on the original price is 1/10 × 137.99 = 13.799. The new price will be the original price - the discount.

The new price is 137.99 - 13.799 = $124.191

Tom has a coupon for an extra 5% off the sale price. It means that Tom would pay 5% off $124.191. The amount that Tom would pay will be

124.191 - (5/100 × 124.191) = 124.191 - 6.20955 = $117.98

The difference between the original price and the price that Tom will pay is

137.99 - 117.98 = $20.01

7 0

2 years ago

Hi. I need help with these questions. See image for question. Please answer no 10 and 11

Tanya [424]

9514 1404 393

Answer:

10. (x, y) = (-3/8, 2 9/16)

11. k = -1

Step-by-step explanation:

10. The value of x at the vertex is ...

x = -b/(2a)

x = -(-3)/(2(-4)) = -3/8

The corresponding value of y is ...

y = 2 +(-3/8)(-3 +(-3/8)(-4)) = 2 +(-3/8)(-3/2) = 2 +(9/16)

The vertex is (x, y) = (-3/8, 2 9/16).

11. The discriminant is zero when the roots are equal.

b² -4ac = 0

(k-1)² -4(1)(-k) = 0

k² -2k +1 +4k = 0

k² +2k +1 = 0 . . . . . collect terms

(k +1)² = 0 . . . . . . . . write as a square

k = -1 . . . . . . . . . . . . the value of k that satisfies

Check

x² -2x +1 = (x -1)² = 0 . . . . has equal roots: x=1.

3 0

2 years ago