Answer:

Step-by-step explanation:
Using pythagoras theorem,

Copper: density ≤ 3.4
Iron: density=2.26
Before: 200 t
After: 800 t
Let's simplify step-by-step.<span><span><span>6x</span>−<span>9x</span></span>−5</span><span>=<span><span><span><span><span>6x</span>+</span>−<span>9x</span></span>+</span>−5</span></span>Combine Like Terms:<span>=<span><span><span>6x</span>+<span>−<span>9x</span></span></span>+<span>−5</span></span></span><span>=<span><span>(<span><span>6x</span>+<span>−<span>9x</span></span></span>)</span>+<span>(<span>−5</span>)</span></span></span><span>=<span><span>−<span>3x</span></span>+<span>−5</span></span></span>Answer:<span>=<span><span>−<span>3x</span></span>−<span>5</span></span></span>