ACT B05 Math Q 21-30

Be sure to know the y-intercept form of a line (y = mx + b). You will use that four or five times on every ACT.​

The line on this graph has a y-intercept of 2. 3 x 2 = 6.

​So that eliminates 3 options.

​The slope of this line is positive. Of the two remaining equations, only one has a positive slope. That one is y = 1/2x + 6

​The area of a square is side x side. So the area of a square with sides of 50 cm is 50 x 50 = 2500.

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​The area of a rectangle is length x width. So what time 10 equals 2500? We can write that as 10x = 2500. Divide by ten on both sides to get x = 250

​For this problem we need to multiple (5x² - 6x + 1)(x² - 2).

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​We will get 5x⁴ - 10x² - 6x³ + 12x + x² - 2. We we combine like terms, we get

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​5x⁴ - 6x³ - 9x² + 12x - 2

​Probability is found by taking the desired outcome and placing that over the possible overcomes. In this case that means taking the number of red marbles and put that over the total number of marbles in the bag. So what do we add to the red and the total to make it 3/5?

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