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    How do you solve this?
    'A rectangle has a length (x+16)cm and width x cm. The square has length(3x-2) cm. The area of the rectangle is 16cm^2 more than the area of the square. The area of the square is more than 1cm^2. Find the value of x.
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    Calculate area of rectangle, calculate area of square.
    Question says area of rectangle = area of square + 16
    rearrange and put it into that double bracket quadratic thing to find x or use the quadratic equation init, ull probably get it with dis.
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    (Original post by BT144)
    How do you solve this?
    'A rectangle has a length (x+16)cm and width x cm. The square has length(3x-2) cm. The area of the rectangle is 16cm^2 more than the area of the square. The area of the square is more than 1cm^2. Find the value of x.
    Area of Rectangle = (x + 16)(x)
    Area of Rectangle = x² + 16x

    Area of Square = (3x-2)(3x-2)
    Area of Square = 9x² - 12x + 4

    8x² - 28x + 20 = 0

    Divide by 4

    2x² - 7x + 5 = 0

    (2x - 5)(x - 1) = 0

    x = 5/2 or x = 1

    x therefore = 5/2
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    (Original post by Kyber Ninja)
    Area of Rectangle = (x + 16)(x)
    Area of Rectangle = x² + 16x

    Area of Square = (3x-2)(3x-2)*
    Area of Square = 9x² - 12x + 4

    x² + 16x - 9x² + 12x + 4 = 16

    (For simplicity, I will multiply by -1 now)

    -x² - 16x + 9x² - 12x - 4 = -16

    8x² - 28x + 12 = 0

    Divide by 4

    2x² - 7x + 3 = 0

    (2x - 1)(x - 3) = 0

    x = 1/2 or x = 3

    x therefore = 3
    The answer is '1 or 2.5.' How?
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    (Original post by BT144)
    The answer is '1 or 2.5.' How?
    cos hes wrong lmaoaoaoaoaooaoaoaoaoaoao
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    (Original post by BT144)
    The answer is '1 or 2.5.' How?
    Oo, my bad it's 8x² - 28x + 20 = 0

    then you should be able to work your way done from that
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    (Original post by BT144)
    The answer is '1 or 2.5.' How?
    he did it right but on his 5th line of writing he wrote +4 instead of -4; he didnt change the sign after switching it to the other side
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    (Original post by humayun.h)
    he did it right but on his 5th line of writing he wrote +4 instead of -4; he didnt change the sign after switching it to the other side
    Thank you, edited for future reference.

    Also good spot
 
 
 
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