Answer:
26; the cheetah's rate in miles per hour
Step-by-step explanation:
−<span>3<span>(<span><span>4a</span>−<span>5b</span></span>)</span></span><span>=<span><span>(<span>−3</span>)</span><span>(<span><span>4a</span>+<span>−<span>5b</span></span></span>)</span></span></span><span>=<span><span><span>(<span>−3</span>)</span><span>(<span>4a</span>)</span></span>+<span><span>(<span>−3</span>)</span><span>(<span>−<span>5b</span></span>)</span></span></span></span><span>=<span><span>−<span>12a</span></span>+<span>15<span>b</span></span></span></span>
We know that,
Julia can finish a 20-mile bike ride in 1.2 hours.
The distance Julia travels is 20 miles and the time she takes is 1.2 hours.
So, Julia's speed = 
= 16.67 mph
Katie can finish the same bike ride in 1.6 hours.
The distance Katie travels is 20 miles and the time she takes is 1.6 hours.
So, Katie's speed = 
= 12.5 mph
Now, to find how much faster Julia rides than Katie we subtract Katie's speed from Julia's speed.
So, 16.67 mph - 12.5 mph = 4.17 mph = 4.2 mph (approximately)
Thus, Julia rides 4.2 mph faster than Katie.
The three numbers are 52, 53, 54.
52+53=105 105+54=159
The formula for the discriminant is b^2-4ac. The formula you wote is in the form of
ax^2+c=0, so first, you need to bring that -2 to the left. When you do that, you get (the original equation would be ax^2+bx+c but you have no bx.)
3x^2-8
So, since there's no b, it would be
b^2-4ac
0^2-4(3)(-8
-12 x -8
96
