If Isaac uses a coupon entitling him to a 25% discount off the purchase price before tax, how much will his bill be? Assume that

Answer:

Davide is 10 years old.

L'età di Davide è 10.

Step-by-step explanation:

The average ages of Aldo, Bruno, Carlo, and Davide amount to 16 years.

Let’s denote:

x for Aldo's age.

y for Bruno's age.

z for Carlo's age.

w for Davide's age.

The average for all four is 16 years.

This gives us:

Excluding Davide, the average age of the other three is 18. Therefore:

Substituting into the original equation:

Hence, Davide’s age is indeed 10.

L'età di Davide è 10.

Answer:

To find the number of genuine solutions for a system of equations consisting of a linear equation and a quadratic equation

1) With two variables, say x and y, rearrange the linear equation to express y, then substitute this y in the quadratic equation

After that, simplify the resulting equation and determine the number of real roots utilizing the quadratic formula, for equations of the type 0 = a·x² - b·x + c.

When b² exceeds 4·a·c, two real solutions emerge; if b² equals 4·a·c, there will be a single solution.

Step-by-step explanation:

This situation exemplifies the distributive property, where the number outside the parentheses impacts all the terms within through multiplication. Therefore, the resulting action here is:

<span>The 4 should be multiplied by each term found inside the parentheses.

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