Answer:
Step-by-step explanation:
Let her brother's age be x
Sarah is 2x + 4
A. 30 sixth graders
b. 12 sixth graders
c. If the school has 40 students and the total of students is 70, the number of sixth graders is x
d. 36 students
The dimensions would be 40 m by 40 m.
To maximize area and minimize perimeter we make the dimensions as close to equal as possible. Since we only need fencing on 3 sides, 120/3 = 40; we can use 40 for each side.
Answer:
Mistake: -3-5=-2, -3-5=-8
Step-by-step explanation:
-3-(7x+5)+9x=-8+3x+10
-3-7x-5+9x=4x+2
-8+2x=4x+2
-8-2=4x-2x
-10=2x
-10/2=x
-5=x
Add <span /><span><span><span><span><span><span>12</span></span><span /></span></span><span /></span><span>12</span></span> to both sides
<span /><span><span><span><span><span><span>8</span><span>x</span><span>=</span><span>5</span><span>x</span><span>+</span><span>15</span><span>+</span><span>12</span></span><span /></span></span><span /></span><span>8x=5x+15+12</span></span>
2<span> </span>Simplify <span /><span><span><span><span><span><span>5</span><span>x</span><span>+</span><span>15</span><span>+</span><span>12</span></span><span /></span></span><span /></span><span>5x+15+12</span></span> to <span /><span><span><span><span><span><span>5</span><span>x</span><span>+</span><span>27</span></span><span /></span></span><span /></span><span>5x+27</span></span>
<span /><span><span><span><span><span><span>8</span><span>x</span><span>=</span><span>5</span><span>x</span><span>+</span><span>27</span></span><span /></span></span><span /></span><span>8x=5x+27</span></span>
3<span> </span>Subtract <span /><span><span><span><span><span><span>5</span><span>x</span></span><span /></span></span><span /></span><span>5x</span></span> from both sides
<span /><span><span><span><span><span><span>8</span><span>x</span><span>−</span><span>5</span><span>x</span><span>=</span><span>27</span></span><span /></span></span><span /></span><span>8x−5x=27</span></span>
4<span> </span>Simplify <span /><span><span><span><span><span><span>8</span><span>x</span><span>−</span><span>5</span><span>x</span></span><span /></span></span><span /></span><span>8x−5x</span></span> to <span /><span><span><span><span><span><span>3</span><span>x</span></span><span /></span></span><span /></span><span>3x</span></span>
<span /><span><span><span><span><span><span>3</span><span>x</span><span>=</span><span>27</span></span><span /></span></span><span /></span><span>3x=27</span></span>
5<span> </span>Divide both sides by <span /><span><span><span><span><span><span>3</span></span><span /></span></span><span /></span><span>3</span></span>
<span /><span><span><span><span><span><span>x</span><span>=</span><span><span><span><span>27</span><span /></span><span><span>3</span><span /></span><span><span /><span /></span></span></span></span><span /></span></span><span /></span><span>x=273</span></span>
6<span> </span>Simplify <span /><span><span><span><span><span><span><span><span><span>27</span><span /></span><span><span>3</span><span /></span><span><span /><span /></span></span></span></span><span /></span></span><span /></span><span>273</span></span> to <span /><span><span><span><span><span><span>9</span></span><span /></span></span><span /></span><span>9</span></span>
<span /><span><span><span><span><span><span>x</span><span>=</span><span>9</span></span><span /></span></span><span /></span><span>x=9
</span></span>
