Let x be the length and y be the width2x + 2y = 40x + y = 20change that into y = mx + b formy= 20 – x
Area =xy = x (20-x) = 20x - x^2Area=-x^2+20xcomplete the square:Area=-(x^2 – 20x + 100) +100=-(x - 10)^2 + 100This is an calculation of a parabola that opens downward with vertex at (10,100), which means maximum area of 100 happens when x, the length=10)Dimensions of the rectangle with maximum area? 10 yds. by 10 yds., a square.
Answer:
its 61.4x+15
Step-by-step explanation:
<em>*To solve an inequality, it's the same as solving an equation; isolate the variable to one side.</em>
For this, all you need to do is divide both sides by -4. And since we are dividing by a <u>negative</u>, flip the inequality sign and your inequality is 
Now to graph this. Since x can be "equal to" 1/4 ( ≤ = less than or equal to), you will have a <u>closed circle on 1/4.</u> And since x can also be "less than" 1/4, <u>the arrow will be going to the left of 1/4.</u>
Answer:
(5, - 4 )
Step-by-step explanation:
Given the 2 equations
2x + 3y = - 2 → (1)
3x - y = 19 → (2)
Multiplying (2) by 3 and adding to (1) will eliminate the y- term
9x - 3y = 57 → (3)
Add (1) and (3) term by term to eliminate y
(2x + 9x) + (3y - 3y) = (- 2 + 57), that is
11x = 55 ( divide both sides by 5 )
x = 5
Substitute x = 5 into either of the 2 equations and solve for y
Substituting into (1)
2(5) + 3y = - 2
10 + 3y = - 2 ( subtract 10 from both sides )
3y = - 12 ( divide both sides by 3 )
y = - 4
Solution is (5, - 4 )
Work out the top subtraction first:
3/9 - 8/12
= 1/3 - 2/3
= 1/3
and the bottom part:-
3/8 * 2 = 6/8 = 3/4
so now we divide -1/3 by 3/4
= -1/3 * 4/3 = -4/9