Answer:
Option (3) will be the answer.
Step-by-step explanation:
Area of a triangle = 
= 
Since, m∠A + m∠B + m∠C = 180°
60° + 60° + m∠C = 180°
m∠C = 180° - 120°
m∠C = 60°
Therefore, ΔABC is an equilateral triangle.
AB ≅ BC ≅ AC ≅12
Sin 60° = 

CD = 6√3
Now area of ΔABC = 
=
= 62.35
≈ 62.4 square units
Therefore, Option (3) will be the answer.
We will use the SAS (SIDE-ANGLE-SIDE) to prove that two triangles are congruent.
Answer:
Kira sent 19 text messages, Goran sent 14 text messages and Joe sent 57 text messages.
Step-by-step explanation:
Let be "k" the number of text messages that Kira sent during the weekend, "g" the number of text messages that Gora sent during the weekend and "j" the number of text messages that Joe sent during the weekend.
We know know that they sent a total of 90 text messages then:

Goran sent 5 fewer messages than Kira. This is:

And Joe sent 3 times as many messages as Kira. Then:

The steps to solve this are:
- Substitute the second equation and the third equatio into the first equation and then solve for "k":

- Substitute this value into the second equation to find "g":

- Substitute the value of "k" into the third equation to find "j":

Answer:
60?
Step-by-step explanation:
Answer:


Step-by-step explanation:

Completing the square is a process of converting a quadratic equation in standard form into vertex form.
The first step in completing the square is grouping the quadratic and linear terms of the quadratic equation.

Factor out the coefficient of the quadratic term,

Now complete the square, add a term to make the grouped part of the equation a complete square, then balance the equation.

Simplify,



The x-coordinate of the vertex of the equation is equal to (-1) times the numerical part of the quadratic term, and the y-coordinate is equal to the constant.
