I'd say by rounding and similar techniques the answer is 468, though it doesn't say all the needed numbers.
To answer your question: Rewrite <span>81<span>x2</span></span> as <span><span>(<span>9x</span>)</span>2</span>.<span><span><span>(<span>9x</span>)</span>2</span><span>−49</span></span>Rewrite 49 as <span>72</span>.<span><span><span>(<span>9x</span>)</span>2</span><span>−<span>72</span></span></span> Both terms are perfect squares, factor using the difference of squares formula, <span><span><span>a2</span><span>−<span>b2</span></span></span>=<span><span>(<span>a+b</span>)</span><span>(<span>a<span>−b</span></span>)</span></span></span> where <span>a=<span>9x</span></span> and <span>b=7</span>.<span><span>(<span><span>9x</span>+7</span>)</span><span>(<span><span>9x</span><span>−7</span></span><span>)</span></span></span>
Answer:
- 5
Step-by-step explanation:
The equation of a line in slope - intercept form is
y = mx + c ( m is the slope (gradient) and c the t- intercept )
y = 3x - 8 ← is in slope- intercept form
with gradient m = 3 and y- intercept c = - 8 , thus
m + c = 3 + (- 8) = 3 - 8 = - 5
Answer:
120 miles/6 hours = 20 mph. You need to do the same for the boat going with the current. 120 miles/ 5 hours = 24 mph.
Step-by-step explanation: