Answers and Step-by-step explanations:
9-18.
a) All the angles of a triangle add up to 180, by definition. So, we can write the expression: 30 + 115 + x = 180.
Then, we can just solve for x by subtracting 30 and 115 from both sides:
x = 180 - 115 - 30 = 35 degrees
b) Again all three angles should add up to 180, so:
x + x + x = 180 ⇒ 3x = 180 ⇒ x = 180/3 = 60 degrees
9-19.
a) These angles add up to 180:
2x + x + 30 = 180 ⇒ 3x + 30 = 180 ⇒ 3x = 150 ⇒ x = 50
2x = 50 * 2 = 100
The missing angles are 100 degrees and 50 degrees.
b) Again, these add up to 180:
x + 10 + x + 90 = 180 ⇒ 2x + 100 = 180 ⇒ 2x = 80 ⇒ x = 40
x + 10 = 40 + 10 = 50
The missing angles are 50 degrees and 40 degrees.
Hope this helps!
Answer:
System
Step-by-step explanation:
Step-by-step explanation:
What this is saying is...20 is a whole number; but 3/4 is not. What they are saying is, if you have to add a mixed number with a whole number, you can add both of the whole numbers together. Then, you add the 3/4 at the end...because it is not a whole number. You can break apart a mixed number by separating the whole number and the fraction.
Hope this helps :)
Answer:
Step-by-step explanation:
Equivalent expressions are expressions that are the same,even though they might look different. If you plug in the same variable value into equivalent expressions they will each give you the same value when you simplify.
