Question

Solve for b, then find the value of b when a = 3

4a=2b-7

Answer 1

Find the width of a rectangle with a perimeter of 90 and a length of 15

Answer 2

To solve for b, we can start by isolating b on one side of the equation.

Given: 4a = 2b - 7

First, let's add 7 to both sides of the equation to move the constant term to the right side:

4a + 7 = 2b

Next, divide both sides of the equation by 2 to solve for b:

(4a + 7)/2 = b

Simplifying further:

2a + 3.5 = b

Now, substituting a = 3 into the equation, we can find the value of b:

2(3) + 3.5 = b
6 + 3.5 = b
9.5 = b

Therefore, the value of b when a = 3 is 9.5.

Answer 3

To solve for the width of a rectangle, we can use the formula for the perimeter of a rectangle:

Perimeter = 2 * (length + width)

Given that the perimeter is 90 and the length is 15, we can substitute these values into the formula:

90 = 2 * (15 + width)

Simplifying further:

90 = 30 + 2 * width

To isolate the width, we can subtract 30 from both sides of the equation:

90 - 30 = 30 - 30 + 2 * width

60 = 2 * width

Finally, divide both sides of the equation by 2 to solve for the width:

60/2 = (2 * width)/2

30 = width

Therefore, the width of the rectangle is 30.