All you do is solve for z. So 8z-13=7. To solve for a variable you have to do the opposite to cancel out the numbers on each side. First you add 13 over to 7 to cancel out 13 on the z side. So 8z=20 is what you have left. Then you divide 8 on both sides to cancel out 8 on the z side. what you are left with is z=2.5. Lastly you plug and check. 8(2.5) - 13 = 7, 20-13=7. And thats correct so z is 2.5.
Answer:
$350,000
Step-by-step explanation:
Let's define:
- s: amount of short-range missiles produced
- m: amount of medium-range missiles produced
- l: amount of long-range missiles produced
From the total production and the ratios we can write the following equations:
s + m + l = 3000
s/m = 3/3 = 1 = m/s
s/l = 3/4 or l/s = 4/3
Dividing the first equation by s, we get:
s/s + m/s + l/s = 3000/s
1 + 1 + 4/3 = 3000/s
10/3 = 3000/s
s = 3000*3/10 = 900
m = 900
l = 4/3*900 = 1200
From the money that the countries plans to use and each missile cost, we can write the following equation:
200,000*s + 300,000*m + cost*l = 870,000,000
Replacing with previous result:
200,000*900 + 300,000*900 + cost*1200 = 870,000,000
cost = (870,000,000 - 200,000*900 - 300,000*900)/1200 = 350,000
Answer:
t=5
Step-by-step explanation:
∵ (t,17) lies on (x,y) plane y=x²-3x+7,t>0
∴ 17=t²-3t+7
t²-3t+7-17=0
t²-3t-10=0
t²-5t+2t-10=0
t(t-5)+2(t-5)=0
(t-5)(t+2)=0
t=5,-2
t>0
so t=5
