No, 21 is a multiple of 7
No. AB is not perpendicular to AC
If the value of a is positive, the line slopes upwards.
To find the slope<span> and y </span>intercept<span>, use the </span><span>y=mx+b</span> formula<span> where </span>m<span> is the </span>slope<span> and </span>b<span> is the y </span>intercept<span>.
</span><span>y=mx+b
</span>Pull the values of m<span> and </span>b<span> using the </span><span>y=mx+b</span> formula<span>.
</span><span>m=<span>7/2</span>,</span><span>b=−2</span><span> where m is the </span>slope<span> and b is the </span>y-intercept