For this case we can make the following rule of three:
21 ------> 70%
x --------> 100%
Clearing x we have:
x = (100/70) * (21)
Rewriting we have:
x = (10/7) * (21)
x = 30
Thus,
21 is 70% of 30
Answer:
21 is 70% of 30

6 0

3 years ago

<img src="https://tex.z-dn.net/?f=4x%20%7B%7D%5E%7B2%7D%20%20%2B%2020x%20%2B%2025" id="TexFormula1" title="4x {}^{2} + 20x + 25

BigorU [14]

$\sf{\qquad\qquad\huge\underline{{\sf Answer}}}$

Let's Solve ~

$\qquad \sf \dashrightarrow \: 4 {x}^{2} + 20x + 25$

$\qquad \sf \dashrightarrow \: 4 {x}^{2} + 10x + 10x + 25$

$\qquad \sf \dashrightarrow \: 2x(2x + 5) + 5(2x + 5)$

$\qquad \sf \dashrightarrow \: (2x + 5) (2x + 5)$

$\qquad \sf \dashrightarrow \: (2x + 5) {}^{2}$

$\sf{\qquad \sf \dashrightarrow \: 4x² + 20x + 25 }$

$\sf{\qquad \sf \dashrightarrow \: (2x)² + (2 \sdot 2x \sdot 5) + (5)²}$

[ it's similar to expression - a² + 2ab + b² that is equal to (a + b)² ]

so, let's use this identity here to factorise :

$\sf{\qquad \sf \dashrightarrow \: (2x + 5)²}$

I hope it was helpful ~

3 0

2 years ago

Identify a pattern and find the next number in the pattern.<br> -48, -24, -12, -6

vodka [1.7K]

It's would be plus haft that number (it's a negative) and the next number would be 0

3 0

3 years ago

Read 2 more answers

How much fencing is needed to make the cage area?

horrorfan [7]

Approximately 2,640 feet

8 0

3 years ago