Find the equation of the line that is perpendicular to y = 2x +7 and has the same y-intercept as y = 8x - 1

What does x = in this equation x+3+2x=x+5

Thales was an ancient philosopher familiar with similar triangles. one story about him says that he found the height of a pyramid by measuring its shadow and his own shadow at the same time. if the person is 5-ft tall, what is the height of the pyramid in the drawing?

What is the value of m in the equation 1/2 m - 3/4n=16 when n=8