Answer:
a = x² + 3x - 40
Step-by-step explanation:
a = l * w
a = (x - 5)(x + 8)
a = x(x + 8) - 5(x + 8)
a = (x² + 8x) + (- 5x - 40)
a = x² + 3x - 40
18 cm is correct .
Step-by-step explanation:
The sum of two smaller sides is greater that the largest side.
It is given that the two sides of a triangle measure 8 cm and 15 cm.
Case 1: Let 8 cm and 15 cm. are smaller side. So,
<em>Third side < 8 + 15</em>
<em>Third side < 23</em>
<em>It means 3rd side must be less than 23</em>
<em>Case 2: Let 15 cm is the largest side.</em>
<em>15 < Third side + 8</em>
15 - 8 < Third side
7 < Third side
It means 3rd side must be greater than 7.
Since only 18 is less than 23 and greater than 7, therefore the possible length of third sides is 18 cm and option 2 is correct.
Answer:
1,3,5
Step-by-step explanation:
81 is a perfect square so it can be written as an integer
11.8 is rational because it can be written as a fraction (107/9)
sqrt(6) isn't a perfect square so it is irrational
3/7 is a fraction so it is rational
8.57 is a terminating decimal so it is rational
Answer:
(a) draw the graph using these coordinates :
(0,-1) and (3,1)
(b) x = 3
Answer:
An apple costs $2.25. A mango costs $1.25.
Step-by-step explanation:
Let a = price of 1 apple.
Let m = price of 1 mango.
Cameron:
4 apples + 7 mangoes ----> total $17.75
4a + 7m = 17.75
Gavin:
2 apples + 5 mangoes ----> total $10.75
2a + 5m = 10.75
We have a system of 2 equations in 2 unknowns.
4a + 7m = 17.75
2a + 5m = 10.75
We can use the elimination method to eliminate the variable <em>a</em>. Rewrite the first equation. Multiply both sides of the second equation by -2 and write below it. Then add the equations.
4a + 7m = 17.75
(+) -4a - 10m = -21.5
---------------------------------
-3m = -3.75
Divide both sides by -3.
m = 1.25
<em>A mango costs $1.25.</em>
Now we use the first equation and substitute 1.25 for <em>m</em> and solve for <em>a</em>.
4a + 7m = 17.75
4a + 7(1.25) = 17.75
4a + 8.75 = 17.75
4a = 9
a = 2.25
<em>An apple costs $2.25.</em>
Answer: An apple costs $2.25. A mango costs $1.25.