The answer is C, the first number in the equation is going to be multiplied separately by the ones inside the parentheses, which is that number distributing.

3 0

2 years ago

find the value of x of given figure and solve this question step by step plzz help question number D

Alinara [238K]

Answer:

x=15 cm

Step-by-step explanation:

The two triangles in the diagram are:

ABC and BDC

First we have to find the third side (hypotenuse) of BDC so that we can use it to find the value of x.

Hypotenuse is the largest side of a triangle which is usually in front of the right angle.

So in BDC

$Base = BD =10cm\\Hypotenuse = BC = ?\\Perpendicular = CD = 2\sqrt{11}cm$

Applying Pythagoras theorem:

$(Hypotenuse)^2 = (Base)^2 + (Perpendicular)^2\\BC^2 = BD^2 + CD^2\\BC^2 = (10)^2 + (2\sqrt{11})^2\\BC^2 = 100+(2^2 * 11)\\BC^2 = 100+(4*11)\\BC^2 = 100+44\\BC^2 = 144\\\sqrt{BC^2} = \sqrt{144}\\BC = 12cm$

Solving for triangle ABC

$Base = BC = 12 cm\\Perpendicular = AB = 9 cm\\Hypotenuse = AC = x\\$

Applying Pythagoras theorem

$AC^2 = BC^2+AB^2\\x^2 = (12)^2 + (9)^2\\x^2 = 144+81\\x^2 = 225\\\sqrt{x^2} = \sqrt{225}\\x = 15cm$

Hence,

x=15 cm

8 0

1 year ago

Which value of x satisfies both -9x+4y=8 and -3x-y=4 given the same value of y?

Deffense [45]

The value of x satisfies both -9x + 4y = 8 and -3x - y = 4 given the same value of y is $-\frac{8}{7}$

Step-by-step explanation:

The system of equations has two equations:

-9x + 4y = 8
-3x - y = 4

Let us solve the system of equations to find the value of x and substitute it in the two equations to check if it gives the same value of y in the two equations

∵ -9x + 4y = 8 ⇒ (1)

∵ -3x - y = 4 ⇒ (2)

- Multiply equation (2) by 4 to make the coefficients of y in the

two equations have same value and different signs

∴ -12x - 4y = 16 ⇒ (3)

- Add equations (1) and (3) to eliminate y

∴ -21x = 24

- Divide both sides by -21

∴ x = $-\frac{8}{7}$

Let us substitute this value of x in equations (1) and (2) to find y

∵ -9( $-\frac{8}{7}$ ) + 4y = 8

∴ $\frac{72}{7}$ + 4y = 8

- Subtract $\frac{72}{7}$ from both sides

∴ 4y = $-\frac{16}{7}$

- Divide both sides by 4

∴ y = $-\frac{4}{7}$

∵ -3( $-\frac{8}{7}$ ) - y = 4

∴ $\frac{24}{7}$ - y = 4

- Subtract $\frac{24}{7}$ from both sides

∴ - y = $\frac{4}{7}$

- Divide both sides by -1

∴ y = $-\frac{4}{7}$

The value of x satisfies both -9x + 4y = 8 and -3x - y = 4 given the same value of y is $-\frac{8}{7}$

Learn more:

You can learn more about the system of equations in brainly.com/question/2115716

#LearnwithBrainly

5 0

2 years ago