Step-by-step explanation:
y=6+4x, as equation (iii)
=> -5x-(6+4x)=21
=> -5x-6-4x=21
=> -5x-4x-6=21
=> -9x-6=21
=> -9x=21+6
=> -9x=27
x= -3, by dividing both sides by -9
So, by inserting x in the first equation,
=> -4(-3)+y=6
=> 12+y=6
=> y=6-12
=> y= -6.
Therefore, x= -3 and y= -6
Answer:
20 4/7 inches
Step-by-step explanation:
Take 12 feet and convert to inches
1 ft = 12 inches
12 * 12 = 144 inches
Divide by 7
144/7 =20 with 4 left over
20 4/7 inches
20 of the students would be 6th graders, hope that helps!
D.
Step-by-step explanation:
because cos0 = b/h
so cos0 = 8/15
the yearly increase of x% assumes is compounding yearly, so let's use that.

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