Answer:
Step-by-step explanation: add the equations
2x² = 30
x² = 15
y² = 12 - 15
= -3
x4 -y4 = 15² - (-3)²
= 216
-1, because the equation for the slope is y2-y1/x2-x1. So let's bring the y value in the second set of point, which is 20, and bring the first y value in the first set of points, which is 5. 20-5 is 15. Now let's subtract the x values. So the second x from the second parentheses x value is -7, and the first x value from the first parentheses is 8. -7-8 is -15. Now we have this division equation, 15/-15, which is -1. So therefore, the slope of the line will be -1.
the idea being, you multiply the "x" by some power of 10 that moves the repeating part to the left of the decimal point and the split it like above.
An equation can be used to predict values from a pattern by merely substituting any value to determine the equivalent value. An example is the geometric series which has a standard equation of an = a1 * r^(n-1) and is used to predict the nth term of the series
