stuck on this question:
y=-1/5 * 2^x intersects y=16-2^x at the point "P"
show that the x coordinate of point P is a root of the equation
2^x = 20
could you please show how you do it thanks
y=-1/5 * 2^x intersects y=16-2^x at the point "P"
show that the x coordinate of point P is a root of the equation
2^x = 20
could you please show how you do it thanks
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-1/5 * 2^x = 16 - 2^x
Add 2^x to each side.
2^x - 1/5 * 2^x = 16
Factorise.
(1- 1/5)*2^x = 16
(4/5) * 2^x = 16
Multiply by 5/4.
2^x = 80/4
2^x = 20
Add 2^x to each side.
2^x - 1/5 * 2^x = 16
Factorise.
(1- 1/5)*2^x = 16
(4/5) * 2^x = 16
Multiply by 5/4.
2^x = 80/4
2^x = 20