Question

If 7p + 5q = 2 and 8p - 9q = 17, then -p + 14q =

Answer 1

set up a system of equations with the first two equations.

7p + 5q = 2
8p -9q = 17
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solve for either p or q.

then solve for the other variable.

use the two values to solve the equation (-p+14q)

Answer 2

how do i solve for p or q?

Answer 3

7p + 5q = 2
8p -9q = 17
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multiply the top by 9 and the bottom by 5

63p + 45q = 18
40p - 45q = 85
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103p + 0q = 103

103p = 103

p = 1

use equation (7p+5q = 2) to solve for q

7(1) + 5q = 2

5q = 2-7

5q = -5

q = -1

try solving the final equation with these values.