Answer:
7. ∠CBD = 100°
8. ∠CBD = ∠BCE = 100°; ∠CED = ∠BDE = 80°
Step-by-step explanation:
7. We presume the angles at A are congruent, so that each is 180°/9 = 20°.
Then the congruent base angles of isosceles triangle ABC will be ...
∠B = ∠C = (180° -20°)/2 = 80°
The angle of interest, ∠CBD is the supplement of ∠ABC, so is ...
∠CBD = 180° -80°
∠CBD = 100°
__
8. In the isosceles trapezoid, base angles are congruent, and angles on the same end are supplementary:
∠CBD = ∠BCE = 100°
∠CED = ∠BDE = 80°
Answer:
Gina is 12 years old
Step-by-step explanation:
First, we will have to write these statements mathematically and then solve.
Let Gina's age be x, let Gina's brother's age be y and let Gina's sister's age be z.
The second statement"Gina's older sister is twice Gina's age" can be mathematically written as: z =2 x ---------------------------(1)
The next statement "Gina's brother is half Gina's age" can be mathematically written as y = 
---------------------------------------(2)
Then the next statement "the sum of their ages is 42" can be mathematically written as: x + y + z = 42 ----------------------------(3)
We can now proceed to solve;
Substitute equation (1) and equation(2) into equation (3)
x + y + z = 42
x + + 2x = 42
Multiply through by 2
2x + x + 4x = 84
7x = 84
Divide both-side of the equation by 7
= 
x = 12
Therefore, Gina is 12 years old
Answer:
48 cm²
Step-by-step explanation:
The copper part is two equal triangles, find a triangle's area by counting squares and multiply by two.
Total copper=(Triangle area)(2)
=b(h)(½)(2)
=b(h)
=(6)(8)
=48 cm²
Answer:
11
Step-by-step explanation
because i added and subtrcted and minus
Answer:
A system of linear equation could only have 1 solution. This is because the straight lines will only have to meet, cross, or intersect each other once.
A system of linear equation could only have 1 solution. This is because the straight lines will only have to meet, cross, or intersect each other once.
There are many different methods in arriving to the final answer. However, errors cannot be perfectly avoided. One of these errors to mistakenly identify equations as linear. It is important that we know that the equations we are dealing with are of exact or correct characteristics.
Also, if she had used substitution method, she might have mistakenly taken the value of one variable for the other.
