Evaluate each expression when a = -4 and b = 3

1.) ab
2.) 2a + 3b
2.) 2(a - b)​

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Long division setup showing an incomplete calculation. 12 is in the divisor, 6839 is in the dividend, and 5 hundreds and 6 tens is written in the quotient. 6000 is subtracted from 6839 to give 839. an unknown value represented by a box is being subtracted from 839. what number should be placed in the box to complete the division calculation?

Lesson 9-3 for items 8-10, a square is drawn in the coordinate plane, with vertices as shown in the diagram. then the square is reflected across the x-axis. -2 4 8. the function that describes the reflection is (x, y) - a. (x, y-3). b. (x, y-6). c. (-x, y). d. (x,- y).