Next Solving Real-World Problems involving Rational Numbers: Mastery Test
3
Type the correct answer in the box. Use numerals instead of words. If necessary, use / for the fraction bar.
2
The Smiths are sending out a batch of holiday cards. Emily signed 5 of the cards. Then Josh signed 9 of the remaining cards. Tatiana signed 20%
of what Josh had left.
If there were 75 cards in all, how many cards are left to be signed?
There are
cards yet to be signed.

answer is:

1.75 pounds

.632

step-by-step explanation:

6 * 1/10 = 3/5

3*0.01 = 0.03

3/5 + 0.03 = .63

2*0.002 = .002

.63 + 0.002 = .632

x = ±sqrt(10)

step-by-step explanation:

5 - 2x² = -15

subtract 5 from each side

5-5 - 2x² = -15-5

-2x^2   = -20

divide by -2 on each side

-2x^2   /-2= -20/-2

x^2 =10

take the square root on each side

sqrt(x^2 )=±sqrt(10)

x = ±sqrt(10)

check:

5 - 2x² = -15

+sqrt(10)

5 - 2(sqrt(10))² = -15

5 -2(10) = -15

5 -20 = -15

-15 = -15

-sqrt(10)

5 - 2(-sqrt(10))² = -15

5 -2(10) = -15

5 -20 = -15

-15 = -15