51(x - 21) = x + 58
<em><u>Distributive property</u></em>
51x - 1071 = x + 58
<em><u>Subtract x from both sides</u></em>
50x - 1071 = 58
<em><u>Add 1071 to both sides</u></em>
50x = 1129
<em><u>Divide both sides by 50</u></em>
x = 22.58
A triangle is 180°; therefore:
x = 180-52-43
x = 85
x° = 85°
Solution of a set of linear inequalities consists all the ordered pair that satisfy all the linear inequalities in the system.
Y=kx+b
line is perpendicular y=1/3x+6⇒ k=-

=-3
so line y=-3x+a
this line that passes through (-9,12)⇔x=-9, y=12, so 12=-3(-9)+a
12=27+a
a=12-27
a=-15
y=-3x-15
P.s.picture<span> to test solutions <span>in the application</span></span>