Answer:
50.4 km (Answer B)
Step-by-step explanation:
From this information, we are able to create a proportion, 2cm/21km= 4.8cm/x km (x representing the actual distance). After cross-multiplying and simplifying, you get an answer of 50.4km. Hope this helps!
−<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>
Answer:
Option B: 
Step-by-step explanation:
The parabola has its concavity downwards, so we need a function in the model:
With a negative value of 'a'
The vertex is (0,0), so we have that:
The x-coordinate of the vertex is given by the equation:
So we have a function in the model:
With a < 0
The only option with this format is B:
- 4 1/5 = -21/5 = -42/10
-13 1/10 = -131/10
-42/10 - -131/10=
-42/10 + 131/10 = 89/10 = 8 9/10
answer is A
