初一数学计算、去括号、合并同类项、解方程题.(过程要写清楚)1.计算.(1)-1.5-(-11.5) (2)4×(-3)²+6(3)22.5+(-3.3)+(-12.5)+3.3 (4)42×(-2/3)+(-3/4)÷(-0.25)(5)(-4)-丨-8丨+丨-2丨-(-3) (6)(-3)²×[(-2/3)+(-5/9
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![初一数学计算、去括号、合并同类项、解方程题.(过程要写清楚)1.计算.(1)-1.5-(-11.5) (2)4×(-3)²+6(3)22.5+(-3.3)+(-12.5)+3.3 (4)42×(-2/3)+(-3/4)÷(-0.25)(5)(-4)-丨-8丨+丨-2丨-(-3) (6)(-3)²×[(-2/3)+(-5/9](/uploads/image/z/579463-7-3.jpg?t=%E5%88%9D%E4%B8%80%E6%95%B0%E5%AD%A6%E8%AE%A1%E7%AE%97%E3%80%81%E5%8E%BB%E6%8B%AC%E5%8F%B7%E3%80%81%E5%90%88%E5%B9%B6%E5%90%8C%E7%B1%BB%E9%A1%B9%E3%80%81%E8%A7%A3%E6%96%B9%E7%A8%8B%E9%A2%98.%28%E8%BF%87%E7%A8%8B%E8%A6%81%E5%86%99%E6%B8%85%E6%A5%9A%291.%E8%AE%A1%E7%AE%97.%281%29-1.5-%28-11.5%29+%282%294%C3%97%28-3%29%26sup2%3B%2B6%283%2922.5%2B%28-3.3%29%2B%28-12.5%29%2B3.3+%284%2942%C3%97%28-2%2F3%29%2B%28-3%2F4%29%C3%B7%28-0.25%29%285%29%28-4%29-%E4%B8%A8-8%E4%B8%A8%2B%E4%B8%A8-2%E4%B8%A8-%28-3%29+%286%29%28-3%29%26sup2%3B%C3%97%5B%EF%BC%88-2%2F3%EF%BC%89%2B%EF%BC%88-5%2F9)
初一数学计算、去括号、合并同类项、解方程题.(过程要写清楚)1.计算.(1)-1.5-(-11.5) (2)4×(-3)²+6(3)22.5+(-3.3)+(-12.5)+3.3 (4)42×(-2/3)+(-3/4)÷(-0.25)(5)(-4)-丨-8丨+丨-2丨-(-3) (6)(-3)²×[(-2/3)+(-5/9
初一数学计算、去括号、合并同类项、解方程题.(过程要写清楚)
1.计算.
(1)-1.5-(-11.5) (2)4×(-3)²+6
(3)22.5+(-3.3)+(-12.5)+3.3 (4)42×(-2/3)+(-3/4)÷(-0.25)
(5)(-4)-丨-8丨+丨-2丨-(-3) (6)(-3)²×[(-2/3)+(-5/9)]
(7)1/3+1/15+1/35+...+1/9999
2.去括号、合并同类项.
(1)5(2x-7y)-3(4x-10y) (2)(x+y)-[3x+(-x+y)]
3.已知a²+ab=3,b²+ab=-2
(1)求a²+2ab+b²的值 (2)求a²-b²的值
4.解方程.
(1)2x-5=2 (2)-a/2+3=5
(3)2-3x-1/2=7/2+x-14/3 (4)-2(3-2x)=12
初一数学计算、去括号、合并同类项、解方程题.(过程要写清楚)1.计算.(1)-1.5-(-11.5) (2)4×(-3)²+6(3)22.5+(-3.3)+(-12.5)+3.3 (4)42×(-2/3)+(-3/4)÷(-0.25)(5)(-4)-丨-8丨+丨-2丨-(-3) (6)(-3)²×[(-2/3)+(-5/9
(1)-1.5-(-11.5) =-1.5+11.5=10
(2)4×(-3)²+6=4x9+6=36+6=42
(3)22.5+(-3.3)+(-12.5)+3.3 =22.5-12.5-3.3+3.3=10
(4)42×(-2/3)+(-3/4)÷(-0.25)=-28+3/4x4=-28+3=-25
(5)(-4)-丨-8丨+丨-2丨-(-3)=-4-8+2+3=-7
(6)(-3)²×[(-2/3)+(-5/9)]=9x(-6/9-5/9)=-9x11/9=-11
(1)5(2x-7y)-3(4x-10y)=10x-35y-12x+30y=-2x-5y
(2)(x+y)-[3x+(-x+y)]=x+y-(3x-x+y)=x+y-2x-y=-x
(1)a²+2ab+b²=(a²+ab)+(b²+ab)=3+(-2)=1
(2)a²-b²==(a²+ab)-(b²+ab)=3-(-2)=5
(1)2x-5=2 2x=-3 x=-2/3
(2)-a/2+3=5 -a/2=5-3=2 -a=2x2=4 a=-4
(3)2-3x-1/2=7/2+x-14/3 2-1/2-7/2+14/3=x+3x 8/3=4x x=32/3
(4)-2(3-2x)=12 -3+4x=12 4x=12+3=15 x=4/15