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3 years ago

Can someone please help me with this I’m struggling

Mathematics

2 answers:

iragen [17]3 years ago

8 0

Answer:

Equation: $70=(x+3)x$

x = -10 or x = 7

x = 7 (width can't be negative)

x + 3 = 10

Step-by-step explanation:

Represent the width of the rectangle by x. "The length of a rectangle EXCEEDS the width by 3" means the length is 3 LONGER than the width, so the length is represented by the expression x + 3.

Area = (length)(width)

70 = (x + 3)x

Multiply out the right side.

$70=x^2+3x\\x^2+3x-70=0$

Factor the left side.

$(x+10)(x-7)=0$

Each binomial could equal 0, so

$x+10=0 \text{ or }x-7=0\\x=-10\text{ or }x=7$

The negative solution does not make sense as the width of a rectangle.

x = 7, making the length, x + 3 = 10

Romashka-Z-Leto [24]3 years ago

7 0

Answer:

Pls mark this as brainiest

Step-by-step explanation:

Area of the rectangle = length x breadth

consider 'x' to be width

therefore length = x+3

area = (x+3)*x

Area = 70 square

x = 7

x+3 = 7+3

= 10

verification

7 x 10

= 70

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