Help with proofs please

riadik2000 [5.3K]

Answer: -5/21.

Step-by-step explanation:

$\frac{2}{5}*[\frac{-3}{7} +(\frac{-1}{6})]=\frac{2}{5} *(-\frac{3}{7} -\frac{1}{6}) =\frac{2}{5}*(-\frac{3*6+1*7)}{7*6} )=\frac{2}{5}*(-\frac{18+7}{42})=\frac{2}{5}*(-\frac{25}{42})=-\frac{5}{21} .$

Good luck an' have a nice day!

8 0

1 year ago

Read 2 more answers

Marco was shopping for markers and lead pencils. The cost of markers is $4, and the cost of each lead pencil is $3. If Macro can

never [62]

This shows that Marco can buy at most 5 pencils

<h3>Inequalities</h3>

Let the price of each pencil Marco can buy be "x"

If the cost of markers is $4, and the cost of each lead pencil is $3 with at most $15 spent, hence;

4 + 3x ≤ 15

Subtract 4 from both sides

3x ≤ 15

x ≤ 15/3

x ≤ 5

This shows that Marco can buy at most 5 pencils

Learn more on inequalities here:

brainly.com/question/24372553

8 0

2 years ago

Read 2 more answers

Can someone explain this to me not only answers make sure to make it clean then i will mark brainliest please i really need an e

Igoryamba

Answer:

Since the sum of the angles equal to 720, you have to add all the angles to add to 720 and then solve for x, in which would look like this (x+2)+(x-4)+(x+6)+(x-3)+(x+7)+(x-8)=720, which is simplified to (6x)=720, in which will make x=120. Next, since its angle E, you plug in tha x value, (120+6), in which the ANSWER IS 126 DEGREES

Step-by-step explanation:

Hope this help ^w^

4 0

2 years ago

For every 5 pages in a book Fred reads, Lonnie reads 4 pages. In 1 hour, they read a combined total of 36 pages. How many pages

nydimaria [60]

Answer:

Hence the number of pages read by Lonnie is 16 pages when they read a combined of 36 pages.

Step-by-step explanation:

The table that can be formed by the rate at which they study the number of pages of a book is:

Fred Lonnie total

5 4 9

10 8 18

15 12 27

20 16 36

That means when they read a combined of 36 pages.

Then the number of pages read by Fred is 20 pages.

and the number of pages read by Lonnie is 16 pages.

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Also it could be done as :

Let Fred reads 'x' pages.

so, the number of pages read by Lonnie is: (4/5)x

Hence,

x+(4/5)x=36

on solving this linear equation we have:

x=20

and (4/5)x=16

)

Hence the number of pages read by Lonnie is 16 pages when they read a combined of 36 pages.

3 0

3 years ago

2x-5y+5z=-10<br> 5x-4y+3z=-19<br> X-y+5z=17

yarga [219]

Answer:

x = -125/71 , y = 448/71 , z = 356/71

Step-by-step explanation:

Solve the following system:

{2 x - 5 y + 5 z = -10 | (equation 1)

5 x - 4 y + 3 z = -19 | (equation 2)

x - y + 5 z = 17 | (equation 3)

Swap equation 1 with equation 2: