A2a
Practice - Plugging in Numbers
TRY TO ANSWER IN TWO AND A HALF MINUTES.
QUESTIONS
QUESTIONS
1. Evaluate 2x -4(4y-3)+5xz when x=-3, y=2, and z=1.
2. What is 3(2x - y) + (3 + x)² when x = 4 and y = 5?
3. The cost of a shipment is $25.60 times the number of boxes plus $14.00 times the number of colors times the number of boxes minus one). What is the cost of 4 boxes and 3 colors?
4. If x = -3 and y = 5, what is 2x²-3xy-4y² ?
5. If f(x) = 2x² -3x+5, what is f(0)?
ANSWERS
1. 2(-3) -4(4x2 -3) + 5(-3)1, = -6 -4(5) -15 = -6 -20 -15 - -41. You could put the first version directly into the built-in calculator.
2. 3(2x4 - 5) + (3+4) ² = (3x3) + 7² = 9 +49 = 58.
3. $25.60(4) + $14.00(3x3) = $102.40 + $126.00 = $228.40.
4. 2(9) - 3(-15) - 4(16) = 18 + 45 - 64 = -1.
5. Five.
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