X = Lilys weight
x + 34 = Arthurs weight
4x - 180 = combined weight
x + x + 34 = 4x = 180
2x + 34 = 4x - 180
-2x -2x
_________________
34 = 2x -180
+180 + 180
_______________
214 = 2x
107 = x which is Lily's weight
141 = x + 34 which is Arthur's weight
The total weight is 248
which is the answer that you get when you do 4(107) = 180 or
428 -180 = 248
<span>This is the equation made from the problem where x=mystery number
</span><span>2x+3(x+1)=4(x-1)</span><span>
</span><span>Now let's solve for x!
</span><span>
</span><span>We start by distributing 3 into (X+1)
</span><span>
</span><span>3(x)=3x and 3(1)=3
</span><span>
</span><span>Now our equation is 2x+3x+3=4(x-1)
</span><span>
</span><span>Let's combine both x values on the left side of the equation: 2x + 3x=5x
</span><span>
</span><span>We now have 5x+3=4(x-1)
</span><span>
</span><span>Let's distribute 4 into (x-1)
</span><span>
</span><span>4(x)=4x and 4(-1)=-4
</span><span>
</span><span>Now our equation is 5x+3=4x-4
</span><span>
</span><span>subtract 3 form both sides
</span><span>
</span><span>5x=4x-7
</span><span>
</span><span>subtract 4x from both sides
</span><span>
</span><span>x=-7
</span><span>
</span><span>Yay! So the number she is thinking of is -7!</span><span>
</span>
35.4% expressed as a decimal is .354
*Anchor: if you got 100% on your test, you got 1 whole test right.
Notice how I moved the decimal back two places to change 100% to 1
*An anchor is something that helps you remember what to do in the future. Use the anchor above to help you remember which way to move the decimal point when you change a percent to a decimal.