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3 years ago

I need help with number 5 please

Mathematics

2 answers:

SIZIF [17.4K]3 years ago

8 0

Answer:

4 $\sqrt{14}$

Step-by-step explanation:

Using the rule of radicals

$\sqrt{a}$ × $\sqrt{b}$ ⇔ $\sqrt{ab}$

Simplify radicals, that is

$\sqrt{56}$

= $\sqrt{4(14)}$

= $\sqrt{4}$ × $\sqrt{14}$ = 2 $\sqrt{14}$

$\sqrt{126}$

= $\sqrt{9(14)}$

= $\sqrt{9}$ × $\sqrt{14}$ = 3 $\sqrt{14}$

Then

$\sqrt{56}$ - $\sqrt{14}$ + $\sqrt{126}$

= 2 $\sqrt{14}$ - $\sqrt{14}$ + 3 $\sqrt{14}$

= 4 $\sqrt{14}$

VMariaS [17]3 years ago

6 0

The answer is the second one 4 √14

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The following triangle shows the length of each side using expressions.

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Answer:

A). 2(2n+7)+3n

B). 2(2(8)+7)+3(8)
2(16+7)+ 24
2(23)+24
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4 0

3 years ago

harlie invests $325 in an account that pays 8% simple interest for 15 years. Use the simple interest formula, I = P ∙ r ∙ t, to

Alina [70]

$390 is the interest will Charlie’s initial investment earn over the 15-year period. The money does Charlie have after the 15 years is $715.

Step-by-step explanation:

Harlie invests $325 in an account.

Principal, P = $325
Interest rate, r = 8% ⇒ 0.08
Number of years, t = 15

The formula to find the interest will Charlie’s initial investment earn over the 15-year period :

⇒ $I = Prt$

⇒ $325\times 0.08\times15$

⇒ $390$

Therefore, $390 is the interest will Charlie’s initial investment earn over the 15-year period.

Money Charlie has after 15 years :

It is given by the formula,

⇒ Amount = Principal + Interest.

⇒ 325 + 390

⇒ 715 dollars.

∴ The money does Charlie have after the 15 years is $715.

3 0

3 years ago

Read 2 more answers

Harold has 4 classes each morning. Each class is 1 hour long, and there are 10 minutes between classes. The first class is at 8

Viktor [21]

The fourth class ends at 12:30 pm

Solution:

Given that Harold has 4 classes each morning

Each class is 1 hour long, and there are 10 minutes between classes

The first class is at 8 A.M

To find: Time at which fourth class ends

Since each is 1 hour long and 10 minutes gap between classes

First class = 8 A.M to 9 A.M

Second class = 9:10 A.M to 10 : 10 AM

Third class = 10 : 20 AM to 11 : 20 AM

Fourth class = 11 : 30 AM to 12 : 30 PM

Thus the fourth class ends at 12:30 pm

4 0

3 years ago

According to exponent rules,when we divide the expressions we ________ the exponents.

Greeley [361]

Answer:

Subtract

Step-by-step explanation:

According to the Quotient Of Powers Property to divide two powers with the same base, you subtract the exponents.

Ex: 9^12 - 9^9 = 9^3

5 0

3 years ago

There are 8 tennis players in a round robin tournament, which means each team will play every other team once. How many matches

Aliun [14]

<h3>Answer: 28</h3>

==========================================================

Explanation:

Method 1

Imagine a table with 8 rows and 8 columns to represent all possible match-ups. You can actually draw out this table or just think of it as a thought experiment.

There are 8*8 = 64 entries in the table. Along the northwest diagonal, we have each team pair up with itself. This is of course silly and impossible. We cross off this entire diagonal so we drop to 64-8 = 56 entries.

Then notice that the lower left corner is a mirror copy of the upper right corner. A match-up like AB is the same as BA. So we must divide by 2 to get 56/2 = 28 different matches.

----------------------------------

Method 2

There are 8 selections for the first slot, and 8-1 = 7 selections for the second slot. We have 8*7 = 56 permutations and 56/2 = 28 combinations.

----------------------------------

Method 3

Use the nCr combination formula with n = 8 and r = 2

$n C r = \frac{n!}{r!(n-r)!}\\\\8 C 2 = \frac{8!}{2!*(8-2)!}\\\\8 C 2 = \frac{8!}{2!*6!}\\\\8 C 2 = \frac{8*7*6!}{2!*6!}\\\\ 8 C 2 = \frac{8*7}{2!}\\\\ 8 C 2 = \frac{8*7}{2*1}\\\\ 8 C 2 = \frac{56}{2}\\\\ 8 C 2 = 28\\\\$

There are 28 combinations possible. Order doesn't matter (eg: match-up AB is the same as match-up BA).

Notice how the (8*7)/2 expression is part of the steps shown above in the nCr formula.

7 0

2 years ago