Answer:
-3
Step-by-step explanation:
this is x equals to -3
we can divide the 4 to other side
This question is solved applying the formula of the area of the rectangle, and finding it's width. To do this, we solve a quadratic equation, and we get that the cardboard has a width of 1.5 feet.
Area of a rectangle:
The area of rectangle of length l and width w is given by:

w(2w + 3) = 9
From this, we get that:

Solving a quadratic equation:
Given a second order polynomial expressed by the following equation:
.
This polynomial has roots
such that
, given by the following formulas:
In this question:


Thus a quadratic equation with 
Then


Width is a positive measure, thus, the width of the cardboard is of 1.5 feet.
Another similar problem can be found at brainly.com/question/16995958
This question is worded slightly strangely but I believe I understand it.
To eliminate x, multiply the second equation by 8, so that it becomes 4x + .8y= 96
Then you can subtract 4x on the top by 4x on the bottom to eliminate it.
Answer:
744 cubic inches
Step-by-step explanation:
Volume of Styrofoam= volume of big box -volume of glass box
=(10*10*15)-(9*7*12)
=1500-756
=744 cubic inches
The distance between the points A to B is 899.9 feet. After rounding off the nearest integer we get 900 feet as the final answer.
Given we know that CD is perpendicular to AD.
The distance between CD is 139 feet.
As from points A the boat's crew measure the angle of elevation to the beacon as 6°
therefore, m∠A = 6°
Another time the angle of elevation is measured from point B which is 19°.
therefore, m∠DBC = 19°
tan 19° = CD/BD
BD = CD/tan19°
BD = 136/tan 19°
now for tan 6° = CD/AD (tangent is opposite over adjacent)
AD = CD/tan 6°
AD = 136/tan 6°
AB = AD ₋ BD
AB = 136/tan 6° ₋ 136/tan 19°
AB = 1295.2 ₋ 395.3
AB = 900 feet
hence the distance from point A to B is 900 feet.
Learn more about Heights and distances here:
brainly.com/question/2004882
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