4x + 8y = 7
8y = -4x + 7
y = -1/2x + 7/8 this equation has slope = -1/2
line perpendicular to the line 4x + 8y = 7, so the slope = 2
same y -intercept as −3x + 5y = −2
y intercept means x = 0
5y = −2
y = -2/5
so
b = -2/5
answer:
equation:
y = 2x - 2/5