These are easy if you know " FOIL ". That's a procedure that takes you through multiplying two binomials.
FOIL stands for
-- <u><em>F</em></u>irst terms
<span>-- </span><u><em>O</em></u>utside terms
<span>--<em> </em></span><u><em>I</em></u>nside terms
<span>--<em> </em><u><em>L</em></u></span>ast terms
and that's how you keep everything straight while you're doing it.
(ax + b) x (cx + d)
Multiply First terms . . . 'ax' times 'cx' = <em>acx²</em>
Multiply Outside terms . . . 'ax' times 'd' = <em>adx</em>
Multiply Inside terms . . . 'b' times 'cx' = <em>bcx</em>
Multiply Last terms . . . 'b' times 'd' = <em>bd</em>
Now addummup:
(ax + b) x (cx + d) = <em>acx² + adx + bcx + bd</em>
From there, you can look for opportunities to make it look cleaner and prettier ... factoring, combining like terms, etc.
2 a + b = 15.7
Since the sides are equal length, the equation is:
2 · 6.3 + b = 15.7
We can solve it:
12.6 + b = 15.7
b = 15.7 - 12.6
b = 3.1 cm
Answer:
none of the answer choices are correct.
CORRECT ANSWER: 15,190
Is -7/8 equivalent to 49/-56? YES
because
49/7 = 7
-56/7 = 8
so
49/-56
= 7/-8
= -7/8