Sign Up FREE!  Sign In  Classroom Setup  Common Core Alignment  
07262007  #1 
Guest
Posts: n/a

algebra 1 help.?
how whould i solve using the perfect squares method? if posible can you explain why?13. x^2 â€“ 14x + 49A (x â€“ 7)(x â€“ 7)B (x + 7)(x â€“ 7)C (x + 7)(x + 7)Dthis one was incorrect(x â€“ 7)(x + 7)E (x â€“ 7)(x â€“ 7)F This polynomial cannot be factored by using the perfect squares method.16. 4x^4 â€“ 20x^2 + 25A (2x^2 + 5)(2x^2 + 5)B (2x^2 â€“ 5)(2x^2 + 5)this one is not it. C (2x^2 â€“ 5)(2x^2 â€“ 5)D (2x^2 â€“ 5)(2x^2 â€“ 5)E (2x^2 â€“ 5)(2x^2 + 5)F This polynomial cannot be factored by using the perfect squares method.

07262007  #2 
Guest
Posts: n/a

13. Answer E16. Answer DI don't speak English, so it is difficult for me to explain why...

07262007  #3 
Guest
Posts: n/a

1)x^2 â€“ 14x + 49=x^2 7x 7x + 49=x(x7)7(x7)=(x7)(x7)E2)4x^4 â€“ 20x^2 + 25=4x^4  10x^2  10x^2 + 25=2x^2(2x^25)  5(2x^25)=(2x^25)(2x^25)D

07262007  #4 
Guest
Posts: n/a

13: x^2  14x + 49If your expression is a perfect square, then your factors will always be of the formAx + B)(Ax + B)this implies that B is not the answer.Ax+B is a factor.Ax+B = 0=> x = B/AA and B can be either positive or negative. the center term (in this case 14x) is the sum of the two factors. the last term (49) is the product. You should find the two numbers which satisfy these two cases.In this case, lets checkption A: (x7) * (x7)=> (x+7) * (x+7) (taking the ve sign out)=> (x+7)(x+7)factor: x+7x+7 = 0=> x = 7sum of factors: 7 + 7 = 14 (does not work, we need 14)product of factors: 7*7 = 49 (works)option B: ruled out beforehandoption C: same as Aoption D: not correctoption Ex7)(x7)factor: 7product: 7 * 7 = 49 (works)sum = 7 + 7 = 7 7 = 14 (works)therefore your answer is option E______________________________________________16: 4x^4  20x^2 + 25product needed: 25sum needed: 20option B,E is out since the two factors are different.options left: A, C, D, Ftry it out like above and see if that works

07262007  #5 
Guest
Posts: n/a

It is E x^214x+49x^22.x.7+(7)^2(x7)^2 (As (a+b)^2=a^22.a.b+b^2) Ansyou can do it the same way

Thread Tools  
Display Modes  

