Ask question

Ask question

All categories

4 years ago

10

sam had 70 erasers and rulers. after giving away 1/3 of his erasers and 10 rulers, he had an equal number of erasers and rulers

left. how many erasers did he have in the beginning?

1 answer:

Radda [10]4 years ago

4 0

Answer:

36 erasers

Step-by-step explanation:

Let number of erasers be e

let number of rulers be r

We can write:

e + r = 70

and

After giving away, he has

Erasers: 2/3e

Rulers: r - 10

These two are equal, so we can write and solve:

2/3e = r - 10

2/3e + 10 = r

Putting this in initial equation, we have:

e + (2/3e + 10) = 70

5/3e + 10 = 70

5/3 e = 60

e = 36

And rulers is:

r = 2/3(36) + 10 = 34

Hence, he had 36 erasers in the beginning

You might be interested in

Question 4 (1 point)

AnnZ [28]

The answer is test scores

8 0

3 years ago

Match the equations representing parabolas with their directrixes. y + 8 = 3(x + 2)2 y − 14 = -(x − 3)2 y + 7.5 = 2(x + 2.5)2 y

Shkiper50 [21]

Answer:

Part 1) $y+8=3(x+2)^{2}$ -----> $y=-8.08$

Part 2) $y-14=-(x-3)^{2}$ ----> $y=14.25$

Part 3) $y+7.5=2(x+2.5)^{2}$ ----> $y=-7.625$

Part 4) $y-17=-(x-3)^{2}$ -----> $y=17.25$

Part 5) $y+7=(x-4)^{2}$ ----> $y=-7.25$

Part 6) $y-6=-(x-1)^{2}$ ----> $y=6.25$

Step-by-step explanation:

we know that

The equation of a vertical parabola in vertex form is equal to

$y-k=\frac{1}{4p}(x-h)^{2}$

where

(h,k) is the vertex

The directrix is

$y=k-p$

case 1) we have

$y+8=3(x+2)^{2}$

the vertex is the point (-2,-8)

$\frac{1}{4p}=3$

$p=\frac{1}{12}$

The directrix is equal to

$y=-8-\frac{1}{12}=-8.08$

case 2) we have

$y-14=-(x-3)^{2}$

the vertex is the point (3,14)

$\frac{1}{4p}=-1$

$p=-\frac{1}{4}$

The directrix is equal to

$y=14+\frac{1}{4}=14.25$

case 3) we have

$y+7.5=2(x+2.5)^{2}$

the vertex is the point (-2.5,-7.5)

$\frac{1}{4p}=2$

$p=\frac{1}{8}$

The directrix is equal to

$y=-7.5-\frac{1}{8}=-7.625$

case 4) we have

$y-17=-(x-3)^{2}$

the vertex is the point (3,17)

$\frac{1}{4p}=-1$

$p=-\frac{1}{4}$

The directrix is equal to

$y=17+\frac{1}{4}=17.25$

case 5) we have

$y+7=(x-4)^{2}$

the vertex is the point (4,-7)

$\frac{1}{4p}=1$

$p=\frac{1}{4}$

The directrix is equal to

$y=-7-\frac{1}{4}=-7.25$

case 6) we have

$y-6=-(x-1)^{2}$

the vertex is the point (1,6)

$\frac{1}{4p}=-1$

$p=-\frac{1}{4}$

The directrix is equal to

$y=6+\frac{1}{4}=6.25$

5 0

3 years ago

Sarah had 3 1/2 cups of flour. She used 2 1/4 cups of flour for a recipe. How much flour does she have left?

Brums [2.3K]

Answer:

1 and 1/4

Step-by-step explanation:

3 0

3 years ago

Read 2 more answers

If Lady Gaga performed as many songs as Madonna per capita, how many would you expect Lady Gaga to sing?

klio [65]

Answer:

32?.....id.kkkkk.kkkkkkk

4 0

3 years ago

Read 2 more answers

HELP! WILL MARK BRAINLY EST!

blsea [12.9K]

Answer:

answer: B

Step-by-step explanation:

8 0

3 years ago