SOLUTION: If angle ABD= x+25 angle CBD= 3x-10 angle ABC= 75, What is angle ABC? What is angle CBD? I'm homeschooled and I do self study. I have 2nd hand books from regular schools.

Algebra.Com
Question 890082: If angle ABD= x+25
angle CBD= 3x-10
angle ABC= 75,
What is angle ABC? What is angle CBD?

I'm homeschooled and I do self study. I have 2nd hand books from regular schools. So I dont have a manual. And i dont know what the answer is and i cant check. Please do help me thanks!

Answer by Okamiden(22)   (Show Source): You can put this solution on YOUR website!
This MIGHT be a theorem or rule that is simply given to you somewhere in your book, but you can see it for yourself and understand it better! I've attached a picture of what I mean below.
.
Simply, I drew out your 4 points on a graph, at random, to help you notice something:
.
http://i.imgur.com/HkbTsh5.png
.
As you can see, we have this set up. Notice that the angle ABC is simply the angle ABD + angle CBD. It makes sense, because the segment BD is in both these angles, and your book's theorem is probably something like "ABD + DBC = ABC, assuming ABC is the biggest angle".
.
If ABC wasn't the biggest angle, the equation wouldn't work, you'd get a weird result in this case. I don't think the book wants you to explore this possibility.
.
Now that we know ABD + CBD = ABC, it's simple.
.
x+25 + 3x-10 = 75
4x+15=75
x=15
ABD=x+25=40
CBD=3x-10=35

RELATED QUESTIONS

If angle ABD = (3x + 15)° and angle ABC = 94°, and angle CBD = (x + 7)°, what is the... (answered by cleomenius)
ray BD is the bisector of angle ABC. If measure angle ABD = 2x+14 and measure angle CBD = (answered by Fombitz)
a. The measure of angle CBD is 10 less than twice the measure of angle ABD. If D is in... (answered by jojo14344)
If angle abc is 78 degrees and angle abd is 30 degrees then what is the value of angle... (answered by Alan3354)
ANGLE ABC AND ANGLE CBD ARE SUPPLENEBTARY .IT ANGLE CBD MEASURES 70 DEGREES WHAT IS THE... (answered by midwood_trail)
If m-angle ABC= 85 and m-angle ABD= 37, find the m-angle... (answered by JBnovelwriter,ikleyn)
The measurement of angle ABD and angle CBD are in the ratio 2:3. If the measurement of... (answered by Fombitz)
if angle ABC= 94 degrees; then find angle CBD. The measure of angle ABC is (3x-15) and... (answered by cleomenius)
BD is the angle bisector of ABC. If ABD= 2x+14 and CBD= 5x-10, what is the measure of... (answered by Fombitz)