Question
1. which number below is irrational?
a)√4/9 b) √20 c)√121
Why is the number you chose irrational?
2. express in simplest form:
√48-5√27+2√75
3. solve for x: (√x+2)-3=0
a)√4/9 b) √20 c)√121
Why is the number you chose irrational?
2. express in simplest form:
√48-5√27+2√75
3. solve for x: (√x+2)-3=0
Answers
Reiny
1. Which numbers are NOT perfect squares?
2. √48-5√27+2√75
= √16√3 - 5√9√3 + 2√25√3
= 4√3 - 15√3 + 10√3
= -√3
3. I will assume you meant
√(x+2) - 3 = 0
then √(x+2) = 3
square both sides
x+2 = 9
x = 7
since we squared, we MUSYT verify all answers.
if x=7
LS = √(7+2) - 3
= √9 - 3
= 0
= RS
so x = 7
2. √48-5√27+2√75
= √16√3 - 5√9√3 + 2√25√3
= 4√3 - 15√3 + 10√3
= -√3
3. I will assume you meant
√(x+2) - 3 = 0
then √(x+2) = 3
square both sides
x+2 = 9
x = 7
since we squared, we MUSYT verify all answers.
if x=7
LS = √(7+2) - 3
= √9 - 3
= 0
= RS
so x = 7