Answer:
I think the answer is A
Sorry if i am wrong
Step-by-step explanation:
Answer:
Step-by-step explanation:So we know x + y = 21 and 5x +10y = 165 We line them up in columns x + y = 21 5x +10y = 165 To eliminate the x variable, I'll multiply every element in the 1st equation by -5. -5x + -5y = -105 5x + 10y = 165 Now we combine (add) the equations, which eliminates x altogether. 5y = 60 ... y = 12 From there, x + 12 = 21 ... x = 21-12 ... x = 9 You should double check. Do 9 nickles and 12 dimes equal $1.65? A very important thing to remember using this method is to do the same thing to each element in the equation that you change! I hope that helps.
#6
x^2 = 1
x = - 1 and x = + 1
#7
a^2 + 1 = 19
a^2 =18
a^2 =√ 9 <span>√ 2
a = + 3</span>√ 2 and a = - 3<span>√ 2</span>
Answer:
23.13
Step-by-step explanation:
