Answer:
The answer is : x = 9.505 and x = -1.005
Step-by-step explanation:
To solve the quadratic equation use the formula :

Where a is the coefficient of x² , b is the coefficient of x and c is the numerical term
∵ a = 18 , b = -153 and c = -172
∴ 

∴ x = 9.505 and x = -1.005
Answer: Without replacing
Step-by-step explanation:
If you don't replace the first red marble, it decreases the number of red marbles in the mix, making the proportion of blue marbles relatively larger. For example, if there were 5 red and 5 blue marbles, there would be a 50% chance of drawing a blue marble. If the red drawn is not replaced, there is a 5/9 chance of drawing a blue marble, or a 55% chance of drawing one.
Answer:
112 $ is the original price
Step-by-step explanation:

you have to think that the original price multiplied by 0.75 (also known as 75%) gave the result of what he saves i.e 84 $. So we put up an equation with the original price multiplied by 75% which equals the 84 $ he saved on buying that item on sale
X=6
y=7
6+7
= 13
1/2(6) + 7
= 3 +7
=10