Rearranging y = 8x -4y = 12 in the y = mx + b form gives y = 2x - 3
y = 2x - 3
y = mx - 6 (already in y = mx + b form)
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Parallel lines have the same slope.
m = 2
Note that the two lines have the different y-intercepts and are not the same line.
Answer: The tripled tofu is 4 lb. 14 oz. Explanation: So you first want to turn your mass into the same unit, so change the pounds of tofu into ounces. There are 16 ounces in a pound, which means the total mass of the original tofu could be written as (16 oz.) + 10 oz. = 26 oz. tofu. Multiply this by 3, and you have tripled the tofu. 3 * 26 = 78. To simplify it, divide 78 oz by 16 to find pounds, and leave the remainder in ounces. 78/16 = 4 lb. 14 oz tofu.
The desired number is the difference between the number of messages sent by the 16th day and the number sent by the 9th day:
... n = t(16) - t(9)
... n = (40×√16) - (40×√9)
... n = 40×(4 - 3) = 40
40 text messages were sent between the ninth and sixteenth day of the month.