Question

help fast plz is it b ?

Answer 1

@shinalcantara

Answer 2

divide everything by 49.. what you've got?

Answer 3

C?

Answer 4

You can use the ac, b method:

a * c = 49*49 = 2401
b = 98

Two number that add to get b and multiply to get ac. To test if it is a perfect square you try half of b:
98 / 2 = 49
So the two numbers are 49 and 49, they add to give 98 (b) and multiply to give 2401 (ac).

So we can factorise as follows:
\[y=49x^2+49x+49x+49\]
\[y=49x(x+1)+49(x+1)\]
\[y=(49x+49)(x+1)\]
\[y=49(x+1)^2\]

Even though there is a coefficient out the front I think that this is still classed as a perfect square, so d. :)

Answer 5

ty sm! <3

Answer 6

can you help me with one more? :)

Answer 7

Sure, as long as you try it first (if it is the same question) :)

Answer 8

this one :)

Answer 9

Okay, use the method that I showed you above on this equation and you will get a perfect square. The bit in the middle of the brackets will be the length of one side of the square. If you get stuck then I'm always here

Answer 10

mm D ? :) @Riddellikins

Answer 11

That's a correct factorisation but you just need the part in the middle. With the squared it is an expression for the area but without it it is an expression for one side.

Answer 12

so D then? O; sorry im kinda confuzed :(

Answer 13

It's 'A', x-6

Area of square = side length squared
A=s^2

So when we factorise the expression we were given:
A=(x-6)^2

If we equate the two equations we get:
s^2 = (x-6)^2
s = x-6

Therefore the side length is x-6

Make sense now? :)