Subject: Square roots
Name: Pamela
Who is asking: Student
Level: Secondary
Question:
I'M NEW AT THIS SO BEAR WITH ME. I'VE ANSWERED THE QUESTIONS BUT HAVE GOTTEN THEM WRONG AND NEED A LITTLE HELP TO COME UP WITH AN ANSWER A SECOND TIME.
HERE GOES(I WILL USE Q AS THE SYMBOL FOR SQUARE ROOT):
8(Q2) - 5(Q2) + Q2
MY ANSWER WAS 3(Q4)
AS WAS MENTION IT WAS WRONG.
SECOND PROBELM IS
(1 + Q2)^{2}
MY ANSWER WAS 3-6(Q2)
LAST ONE
3/(2-Q5)
MY ANSWER WAS 6+Q5/9
WAIT A MINUTE I HAVE ONE MORE THAT I HAVE NO IDEA HOW TO SOLVE IT IS
(Q2 - Q3) (Q2 + Q3)
I'VE JUST STARTED HOMESCHOOLING AND MY MOM AND DAD ARE NOT TOO GOOD IN MATH SO ANY HELP YOU CAN LEND WOULD BE MUCH APPRECIATED.
PAWS.
Hi Pemela,
A good idea with some of these problems is to replace the square root of 2 with the square root of 9 which is 3. So in the first problem you have eight 3's minus five 3's plus one 3, that is (8 -5 +1) 3's or (4)3's.
Promlem 2: (1 + Q2)^{2}
You have to use the identity (a+b)^{2} = a^{2} + 2ab + b^{2}
and the identity (Q2)^{2} = 2. You seem to have gotten the second one
correct, since you got a 3 in the answer. Perhaps the best is to practice
the first identity using Q9 instead of Q2, because Q9 = 3, and there
you can see where you go wrong.
Problem 3: 3/(2-Q5)
That was close. The denominator should be 4-5=-1 not 4+5=9. You also seem tohave forgotten your parenthesis: 3(2+Q5)/-1 = (6+3Q5)/-1 = -6-3Q5.
Problem 4: (Q2 - Q3) (Q2 + Q3)
The last one uses the difference of squares: (a - b)(a + b) = a^{2} - b^{2}.
Again, try using Q16 and Q9 instead of Q2 and Q3, to make sense out of your answer and check it.
Cheers,
Claude