Plz help will mark brainlest

What is the solution of

kobusy [5.1K]

Answer:

Third option: x=0 and x=16

Step-by-step explanation:

$\sqrt{2x+4}-\sqrt{x}=2$

Isolating √(2x+4): Addind √x both sides of the equation:

$\sqrt{2x+4}-\sqrt{x}+\sqrt{x}=2+\sqrt{x}\\ \sqrt{2x+4}=2+\sqrt{x}$

Squaring both sides of the equation:

$(\sqrt{2x+4})^{2}=(2+\sqrt{x})^{2}$

Simplifying on the left side, and applying on the right side the formula:

$(a+b)^{2}=a^{2}+2ab+b^{2}; a=2, b=\sqrt{x}$

$2x+4=(2)^{2}+2(2)(\sqrt{x})+(\sqrt{x})^{2}\\ 2x+4=4+4\sqrt{x}+x$

Isolating the term with √x on the right side of the equation: Subtracting 4 and x from both sides of the equation:

$2x+4-4-x=4+4\sqrt{x}+x-4-x\\ x=4\sqrt{x}$

Squaring both sides of the equation:

$(x)^{2}=(4\sqrt{x})^{2}\\ x^{2}=(4)^{2}(\sqrt{x})^{2}\\ x^{2}=16 x$

This is a quadratic equation. Equaling to zero: Subtract 16x from both sides of the equation:

$x^{2}-16x=16x-16x\\ x^{2}-16x=0$

Factoring: Common factor x:

x (x-16)=0

Two solutions:

1) x=0

2) x-16=0

Solving for x: Adding 16 both sides of the equation:

x-16+16=0+16

x=16

Let's prove the solutions in the orignal equation:

1) x=0:

$\sqrt{2x+4}-\sqrt{x}=2\\ \sqrt{2(0)+4}-\sqrt{0}=2\\ \sqrt{0+4}-0=2\\ \sqrt{4}=2\\ 2=2$

x=0 is a solution

2) x=16

$\sqrt{2x+4}-\sqrt{x}=2\\ \sqrt{2(16)+4}-\sqrt{16}=2\\ \sqrt{32+4}-4=2\\ \sqrt{36}-4=2\\ 6-4=2\\ 2=2$

x=16 is a solution

Then the solutions are x=0 and x=16

5 0

2 years ago

Create an expression to represent the following<br><br> (picture is included below)

zheka24 [161]

Answer:

7) x + 0.09x, where x is the price of the car

8) x + 0.05x where x is the price of clothing

9) It will take michael about 9.14 minutes to eat 32 cookies.

Step-by-step explanation:

7) 9% of x is the same as 0.09x, so you can write this:

x + 0.09x, where x is the price of the car

8) same thing for this one

x + 0.05x where x is the price of clothing

9) michael can eat cookies at a rate of 21 cookies per 6 minutes, or $\frac{21}{6}$

Because he will be eating them at the same pace, you can write an equation and solve for the variable:

$\frac{21}{6}$ = $\frac{32}{y}$

cross multiply the proportion:

21 × y = 32 × 6

solve:

21y = 192

y ≈ 9.14

It will take michael about 9.14 minutes to eat 32 cookies.

This works because they both simplify to 3.5 cookies per minute

$\frac{21}{6}$ = 3.5

$\frac{32}{9.14}$ = 3.5

6 0

2 years ago

Round to the nearest hundred 1,139

SSSSS [86.1K]

1,100

Because when you round the 39 round down

6 0

2 years ago

5{-3.4k-7} + {3k+21}

nekit [7.7K]

First step is to do distributive property.

so you multiply 5 by -3.4k and -7

your equation now is -17k-35+(3k+21)

Then you add like terms

add -17k+3k to give you -14k-35+21

then you add like terms again

add -35+21 to give you -14

so now your equation is -14k-14

So that is your answer simplified

6 0

2 years ago

Please help anyone with this question

Nikitich [7]

Answer:

0.6

Step-by-step explanation:

1. 9 out of 15 = 9/15

2. Use the calculator to find that 9/15 = 0.6

5 0

2 years ago