How do you find a missing angle simply

Add 1/7 + -1/7 your answer should be reduced to its smallest form and should not be an improper fraction

Find the x-intercept and y-intercept of the line. 3x + 5y = −15

Which linear equations have an infinite number of solutions? check all that apply.  (x  –  3/7)  =  2/7(3/2x  –  9/14)8(x  +  2)  =  5x  –  1412.3x  –  18  =  3(–6  +  4.1x)(6x  +  10)  =  7(x  –  2)4.2x  –  3.5  =  2.1 (5x  +  8)