–6c = –7 − 5c Solve Please

c = 7

Step-by-step explanation:

Isolate the variable c. Note the equal sign, what you do to one side, you do to the other.

First, add 5c to both sides of the equation:

-6c (+5c) = -7 - 5c (+5c)

-6c + 5c = -7

-c = -7

Isolate the variable, c. Divide -1 from both sides of the equation:

(-c)/-1 = (-7)/-1

c = -7/-1

c = 7

c = 7 is your answer.

~

11.71 cm 2

Step-by-step explanation:

Find the area of quadrilateral ABCD

∴ Area of quadrilateral =21d(h1+h2)=21×12×11=6×11=66 cm2

This means that the best equation to use is

equation of the diagonal = d then d* (h1+h2)

We have measure d  *  (h1+h2)  = area

This is how we find the diagonals = a * c + b* d = 2*5+ 3*-5 = -5

We find -5 by looking for the sides of the quadrilateral and its diagonals. If you multiply the lengths of each pair of opposite sides, the sum of these products equals the product of the diagonals

= -5d ( h1 +h2) = -5d ( -0.853 x 2)  = -5 * -2.342 = 11.71

Formulas: For angles measuring 59.1  for a,  71.9 for γ , 161 for β

e = √ a² + b² - 2ab * cos( β )

f = √ b² + c² - 2bc * cos( γ )

When we input we can prove with cos (  β angle)

e  = √ 5² + 2² -  (2 * 5 * 2) cos ( 161 )   = 3.4728

f = √ 5² + 3² - 2* 5 * 3 * cos( 71.9 )  = 5.25

then;

γ1 = arccos( (b² + e² - a²) / 2be )

γ2 = γ - γ1

d = √ c² + e² - 2ce * cos( γ2 )

then;

α = arccos( (a² + d² - f²) / 2ad )

δ = 360° - α - β - γ

p = a + b + c + d

A = √ 4e²f² - ( b² + d² - a² - c² )² / 4

A = √ 4e²f² - ( b² + d² - a² - c² )² / 4

A = 11.71

vertices a = 5  b= 2  c= 3 d= -5

where e = √3.4728 and f = √5.25

=  (2^2 + 5^2 - 5^2 - 3^2 ) =  4+25+25 -9  = (-5^2- √ 4e²f²) = -25 -  18.2322801025= (2025/43.2322801025 =  46.84 /4 = 11.71