Answer:
She should make a rectangle with dimensions 14.4 cm by 4.2 cm.
Step-by-step explanation:
- The diagonal of a rectangle is represented by
. - Area of rectangle is = length×width
- Perimeter of a rectangle = 2(length+width).
Assume x be the width of the rectangle.
The length of the rectangle is to be 6 cm more than twice the width.
The length of the rectangle is= (2x+6) cm
Then the diagonal of the rectangle is 


cm
According to the problem,

Squaring both sides




⇒5x²+45x-21x-189=0
⇒5x(x+9)-21(x+9)=0
⇒(x+9)(5x-21)=0
⇒x+9=0 or, 5x-21=0

⇒x= -9, 4.2
Since the width of a rectangle can not negative.
So, x=4.2 cm
The width of rectangle is = 4.2 cm
The length of the rectangle is =(2×4.2+6)
=14.4 cm
She should make a rectangle with dimensions 14.4 cm by 4.2 cm.
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Answer:
Solution in photo
Step-by-step explanation:
Let's solve your equation step-by-step.<span><span><span>2x</span>+<span>3<span>(<span>x−4</span>)</span></span></span>=<span>x−20</span></span>Step 1: Simplify both sides of the equation.<span><span><span>2x</span>+<span>3<span>(<span>x−4</span>)</span></span></span>=<span>x−20</span></span><span>Simplify: (Show steps)</span><span><span><span>5x</span>−12</span>=<span>x−20</span></span>Step 2: Subtract x from both sides.<span><span><span><span>5x</span>−12</span>−x</span>=<span><span>x−20</span>−x</span></span><span><span><span>4x</span>−12</span>=<span>−20</span></span>Step 3: Add 12 to both sides.<span><span><span><span>4x</span>−12</span>+12</span>=<span><span>−20</span>+12</span></span><span><span>4x</span>=<span>−8</span></span>Step 4: Divide both sides by 4.<span><span><span>4x/</span>4</span>=<span><span>−8/</span>4</span></span><span>x=<span>−2</span></span>Answer: x=−2
You can multiply 3 and 6 together then divide the product by 2
(6*3)/2=18/2=9