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BD bisects <ABC.
m <ABD= 2.5x + 8.6
m<CBD = 3.5x - 3.4
Find m<ABC
Answer:

Step-by-step explanation:
We have an angle ABC and a line BD bisecting it.
If an angle is bisected, then the two formed angles are congruent, that is

Substituting the algebraic expressions for both angles:

Subtracting 8.6 and 3.5x:

Operating:


The two angles are:


As expected, both angles have the same measure.
The measure of the total angle ABC is twice any of those:


Answer:
Step-by-step explanation:
The secants form a proportion where the full length of the secant is the denominator of a fraction where the numerator is the external part of the secant.
7/(x + 7) = 6/(15 + 6) Cross Multiply after combining
7 / (x + 7) = 6/(21)
6 * (x + 7) = 7 * 21 Remove the brackets
6x + 42 = 147 Subtract 42
6x = 147 - 42
6x = 105 Divide by 6
x = 17.5
I think I've done this correctly. If you find an error, please let me know and I'll open it for editing.
Answer:
d
Step-by-step explanation:
The answer will be 4.222222
2/3=x/12
Use cross multiply
2*12=3*x
24=3x
Divided both side by 3
24/3=3x/3
x=8
Check:
2/3=x/12
Substitute x with 8
2/3=8/12
2/3=(8/4)/(12/4)
2/3=2/3. As a result, x=8. Hope it help!