Let S represent Sunaina's age.
Let T represent Tanish's age.
So 2S - T/2 = 40, 4S - T = 80.
Either S - T = 2 or T - S = 2. Let's try both cases.
Either 3S = 78 or 3S = 82.
Since 82 is not a multiple of 3, S = 26.
So Sunaina is 26 years old and Tanish is 24 years old.
-3x^2 - 10x + 5 = 0
Quadratic formula:
-b +/- sqrt[b^2 - 4(a)(c)]/2(a)
So. . . 10 +/- sqrt[(10^2) - 4(-3)(5)]/2(-3)
10 +/- sqrt[100+60]/ -6
10 +/- sqrt[160]/-6
Answer:
On the graphing calculator, use the function normCdf, where
- lower bound = -9999
- upper bound = 210
- mean = 250
- standard deviation = 46
It will result in normCdf(-9999,210,250,46) ≈ 0.192269 or 19.2269%
X intercept- 3.5
y intercept- 2.5