Answer:
f(x) = -60 is your answer
Step-by-step explanation:
Plug in 3 for x
f(x) = 5x² - 7(4x + 3)
f(x) = 5(3²) - 7(4(3) + 3)
Follow PEMDAS. First, solve the parenthesis
3² = 9
4(3) + 3 = 12 + 3 = 15
f(x) = 5(9) - 7(15)
Multiply
f(x) = 45 - 105
Simplify. Subtract
f(x) = 45 - 105
f(x) = -60
f(x) = -60 is your answer
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If we know that Pedro bought 1

pounds of red sand, and 5

pounds of brown sand, and they both cost $4.60, then we just have to add the individual amounts of sand, since they cost the same.

So Pedro bought

lbs of sand overall. Now, we just need to multiply the cost per pound by the total amount of sand he bought.

Pedro spent $31.05 on sand, which is answer choice B.
Hope that helped =)
Answer:
yes
Step-by-step explanation:
The graph is of a function (one output for every input) that also passes the horizontal line test (one input for every output). Hence it is one-to-one.
For a <em>function</em>, the key for it being one-to-one is that it pass the horizontal line test.