How can i find the circumference of a circle with only the diameter given?

Multiply −2x(6x^4−7x^2+x−5) express the answer in standard form. enter your answer in the box.

What is the x-intercept and y-intercept of the equation 2x+1. 2o

If m∠abc = 70°, what is m∠abd? justify your reasoning.  using the addition property of equality, 40 + 70 = 110, so m∠abd = 110°.  using the subtraction property of equality, 70 − 30 = 40, so m∠abd = 30°.  using the angle addition postulate, 40 + m∠abd = 70. so, m∠abd = 30° using the subtraction property of equality.  using the angle addition postulate, 40 + 70 = m∠abd. so, m∠abd = 110° using the addition property of equality.