<span>Kevin is 16
Timothy is 10
------------
check:
4 yrs ago Kevin was 12
4 yrs ago Timothy was 6
Kevin was twice his age
OK</span>
Answer:
x = 4, y = -4
Step-by-step explanation:
9x + 3y = 24
3x + y = 8 divide both sides by 3
y = 8 - 3x subtract 3x from both sides
2y + 4x = 8
2(8 - 3x) + 4x = 8 replace y with 8 - 3x
16 - 6x + 4x = 8 distributive property
-6x + 4x = 8 - 16 subtract 16 from both sides
-2x = -8 divide both sides by -2
x = 4
y = 8 - 3x
y = 8 - 3(4) replace x with 4
y = 8 - 12
y = -4
Answer:
49680
Step-by-step explanation:
Multiply 54,000 by 92%. 100%(this years population)-8%=92%
54000*0.92 = 49680, people one year ago.
Lets call those two unknown numbers a, b and write the info in the problem as equations:
a*b = 30
a + b = 40
lets solve for a in the second equation and substitute in the first:
<span>a + b = 40
</span>a = 40 - b
therefore:
<span>a*b = 30
</span>(40 - b)b = 30
40b - b^2 = 30
b^2 - 40b + 30 = 0
if we apply the general quadratic equation to solve we have:
b = (40 +- √(1600 - 120))/2
b = (40 +- √(1480<span>))/2
</span>b = (40 +- 38.47)/2
There are two solutions:
<span>b1 = (40 + 38.47)/2
</span><span>b1 = 39.24
b2 = (40 - 38.47)/2
</span>b2 = 0.765
lets use the second solution <span>b2 = 0.765, and substitute in the first equation to find a:
</span><span>a*b = 30
</span>a*0.765 = 30
a = 30/0.765
a = 39.216
so the numbers are 39.216 and 0.765
Answer:
the area is: 90 square inches
Step-by-step explanation:
Since you use the same amount of material to create the rectangle, that means that the area of a parallelogram has the same formula as the area of a rectangle. That is:
Area of parallelogram = base x height
In our case: 9 in x 10 in = 90 square inches
