Answer:
- 2
Step-by-step explanation:
5x + 3x = - 10 - 6
8x = -16
x = -2
Answer:
a=3
Step-by-step explanation:
a=3 because 5+4=9 and 9÷3=3
hope this helps!!
looks like the question is not finished. x
Given:
<span>random sample of 520 adults
mean was 150
standard deviation was 4.5.
reported with a 95% confidence level, and the confidence interval for the study was 150 ± 0.39.
The range of </span><span>values that shows the confidence interval for the study is </span><span>149.61 to 150.39
150 + 0.39 = 150.39
150 - 0.39 = 149.61</span>
I: y=(1/2)x+5
II: y=(-3/2)x-7
substitution:
fancy word for insert the definition of one variable in one equation into the other
-> isolate a variable, luckily y is isolated (even in both equations) already
-> substitute y of II into I (=copy right side of II and replace y in I with it):
(-3/2)x-7=(1/2)x+5
-3x-14=x+10
-3x-24=x
-24=4x
-6=x
-> insert x back into I (or II):
y=(1/2)x+5
=(1/2)*(-6)+5
=-3+5=2
elimination: subtract one equation from the other to eliminate a variable, again y is already isolated->no extra work required
I-II:
y-y=(1/2)x+5-[(-3/2)x-7]
0=(1/2)x+5+(3/2)x+7
0=(4/2)x+12
-12=2x
-6=x
-> insert x back into I (or II):
y=(1/2)x+5
=(1/2)*(-6)+5
=-3+5=2
