This is the last question on my
the cost of a cheese pizza is $9.99 plus $0.35 for each additional topping, t.
write an inequality that can be used to represent the cost of a pizza that is at most $12.
what is the most number of toppings that a pizza can have and still be at most $12?

answer:

at most there can be 5 toppings on the pizza.

step-by-step explanation:

first, we need to create our inequality.

we know that 9.99 is the static price, while 0.35 changes with the amount of toppings. this means that 0.35 must be accompianied by a t. next, we need to decide what kind of sign that we need. in this case, it needs to be at most 12. this means that it must be less than or equal to 12, so we will use the sign .

knowing all of this, we can create our inequality

now that we have our inequality, we can solve for t.

we need to keep in mind that we cannot have a decimal value for the number of toppings. this means that we have to round down to 5 toppings.

step-by-step explanation:

30% of $420 is 0.30($420) = $126 and $420 + $126 = $546.

or, 130% of $420 is 1.3($420) = $546.

notice that this is not the $600 original list price with which we started.

why doesn't this work?

the method does not work because 30% of $420 is not the same amount as the 30% of $600. it may seem obvious when stated this way, but it is a very common error made on problems of this type. we cannot just use the same percent and get back to the original amount because we are taking that percent of a different value.

to work problems of this type correctly, it is generally best to write an equation for the situation and then solve.

example: since (100% – 30%)(original price) = (sale price)

70% of the   (original price) is $420.

0.7x   = 420

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x = 600

the original cost was $600.

we may also solve this problem using the two-step method. working the problem in two steps requires us to use more algebra skills. we have to know that x = 1x (identity property of multiplicationtext annotation indicator) and that 1x – 0.3x = 0.7x (subtracting like terms). then we solve the problem as follows:

(original price) – 30%(original price) = sale price

x – 0.3x = 420

0.7x = $420

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x = 600

the original cost was $600.  

note that with both of the above methods we do obtain the correct original amount.

example: after a 5% pay raise, hermione is earning $22,680 per year. what was she earning before the pay raise?

105% of (original salary) = current salary

1.05x = 22,680

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x = 21,600

hermione earned $21,600 per year before the pay raise.

this is an example so maybe you will get how to at least do it!

i suppose it should be (y=2x-5)

step-by-step explanation: