The answer is 60 since the other shape has same answer for that side
        
                    
             
        
        
        
Call the notebooks x, and the pencils y. 
<span>3x + 4y = $8.50 and 5x + 8y = $14.50 </span>
<span>Then just solve as simultaneous equations: </span>
<span>3x + 4y = $8.50 </span>
<span>5x + 8y = $14.50 </span>
<span>5(3x + 4y = 8.5) </span>
<span>3(5x + 8y = 14.5) </span>
<span>15x + 20y = 42.5 </span>
<span>15x + 24y = 43.5 </span>
<span>Think: DASS (Different Add, Similar Subtract). 15x appears in both equations so subtract one equation from the other. Eassier to subtract (15x + 20y = 42.5) from (15x + 24y = 43.5) </span>
<span>(15x + 24y = 43.5) - (15x + 20y = 42.5) = (4y = 1) which means y = 0.25. </span>
<span>Then substitue into equation : </span>
<span>15x + 20y = 42.5 </span>
<span>15x + 5 + 42.5 </span>
<span>15x = 42.5 - 5 = 37.5 </span>
<span>15x = 37.5 </span>
<span>x = 2.5 </span>
<span>15x + 24y = 43.5 </span>
<span>15(2.5) + 24(0.25) </span>
<span>37.5 + 6 = 43.5 </span>
<span>So x (notebooks) are 2.5 ($2.50) each and y (pencils) are 0.25 ($0.25) each.</span>
        
             
        
        
        
Answer:
80%; 30%
Step-by-step explanation:
There is 5 blue marbles, 2 black marbles, and 3 red marbles. In other words, there is a total of 10 marbles. 
There are only 2 black marbles and 8 marbles that are not black. Therefore, the probability of <em>not</em> drawing a black marble is 8/10 or 4/5 or 80%. 
There are only 3 red marbles out of the 10 total marbles. Therefore, the probability of drawing a red marble is 3/10 or 30%. 
 
        
             
        
        
        
Answer:
20% and 95%
Step-by-step explanation:
I know this is correct trust me!
 
        
                    
             
        
        
        
Answer:
2x^3 + 6x^2
Step-by-step explanation:
Volumen = area * height
You already had the area which is: 
x^2 + 3x
and the heigth is 2x
Volumen = (x^2 + 3x)* 2x
Volumen = 2x^3 + 6x^2