F Which conditions are sufficient to prove a quadrilateral is a square?

I need how you found the answers?

lara31 [8.8K]

Answer:

2x + 6 = -18

x + 1 = -11

3x = -36

Step-by-step explanation:

First find the solution! Then you can create your own equations

2x+9=-15

2x=-24

x=-12

Thus u need solutions with:

x = -12

Knowing the equation of a line as:

y = mx + b

we can can start by making y = -12 (our solution)

mx + b = -12

Now we can pick a value for m and b by adding and miltiplying on both sides

We do this to keep both sides equal.

if we make m = 2 and b = 3:

2x + mb = -12*m + 2b

2x + 6 = -24 + 6

2x + 6 = -18

Solving this we also get x = -12, as we expect.

An alternative way to think about it is to imagine that we start with a simple equation and make it more complex. We have our solution:

x = -12 => lets add a b value!

x + b = -12 + b => Lets add a slope (m)

xm + bm = -12m + bm

Giving values for this can give you multiple equation of the same solution.

General Formula:

m(x+b) = m(y+b)

mx + bm = my + bm

8 0

3 years ago

Find b, given that a = 20, angle A = 30°, and angle B = 45° in triangle ABC

Kamila [148]

The side b is opposite to the angle B, applying the law of the sines, we have:

 $\frac{a}{sinA} = \frac{b}{sinB}$
$\frac{20}{sin30^0} = \frac{b}{sin45^0}$
$\frac{20}{ \frac{1}{2} } = \frac{b}{ \frac{ \sqrt{2} }{2} }$
$20* \frac{ \sqrt{2} }{2} = b* \frac{1}{2}$
$\frac{20 \sqrt{2} }{2} = \frac{b}{2}$
$2*b =2*20 \sqrt{2}$
$2b = 40 \sqrt{2}$
$b = \frac{40 \sqrt{2} }{2}$
$\boxed{b = 20 \sqrt{2} }$

6 0

3 years ago

Read 2 more answers

Find the number of ways to listen to 4 CDs from a selection of 8 CDs.

Sati [7]

1680. 8p4, which is 8!/(8-4)!

5 0

4 years ago

Question 1

nevsk [136]

Answer: " n = - 4 " .
__________

Step-by-step explanation:

Given:
-n + 8 = 12 ; solve for "n" ;

Subtract "8" from each side of the equation:

-n + 8 - 8 = 12 - 8 ;

to get:
-n = 4 ;

Which is the same as:
-1n = 4 ;

Divide each side of the equation by "-1" ; to isolate "n" on one side of the equation; and to solve for "n" :

-1n / -1 = 4 / -1 ;

to get:
" n = - 4 " ; which is our answer.
_______________

Now, let's check our answer:
_______________
→ by plugging in our value obtained for "n" ; which is " - 4 " ;
_______________
-(-4) + 8 ≟ 12 ?? ;
_______________

From the "left-hand sign" of the equation:
_______________
" - (-4) = ⁺ 4 " ;
_______________
Note: The opposite of negative value; or the negative of a negative value; is equal to that very positive value.
_______________
⇒ " 4 + 8 ≟ 12 ? ;