The answer would be A.83 if I’m not mistaken, sorry if I’m no help
-8.1
Step-by-step explanation:

<em>Times </em><em>all </em><em>by </em><em>9</em><em> </em><em>to </em><em>get </em><em>rid </em><em>of </em><em>fraction</em>
<em>
</em>
<em>Take </em><em>2</em><em>1</em><em>.</em><em>6</em><em> </em><em>away</em><em> </em><em>from</em><em> </em><em>both</em><em> </em><em>sides</em>
<em>
</em>
<em>Divide</em><em> </em><em>by </em><em>-</em><em>4</em>
<em>
</em>
Answer:
120 > x
Step-by-step explanation:
multiply -4 on both sides, -30 * -4 = 120
since you multiplied by a negative you change the sign
<3
Answer:
b=2
Step-by-step explanation:
we have
9x+12y=21 -----> equation A
6x+8y=7b ----> equation B
we know that
If the system of equations have an infinite number of solutions then the equation A must be equal to the equation B
Multiply equation B by 1.5 both sides
1.5*[6x+8y[=7b*1.5
9x+12y=10.5b ----> equation C
Compare equation A and equation C
9x+12y=21 -----> equation A
9x+12y=10.5b ----> equation C
For the equations to be equal it must be fulfilled that
21=10.5b
solve for b
b=21/10.5
b=2